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Optronics Backup Light for Trucks or Trailers - Submersible - Incandescent - Oval - Clear Lens

Optronics Backup Light for Trucks or Trailers - Submersible - Incandescent - Oval - Clear Lens

Item # BU70CB
Our Price: $9.11
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Trailer Lights
Shipping Weight: 0.27 lbs
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6-1/2" x 2-1/4" Oval. Waterproof incandescent light provides backup light function for trucks or trailers. Shock proof socket protects bulb. Recessed mount with grommet (sold separately). Accepts standard 2-prong plug. Great Prices for the best trailer lights from Optronics. Optronics Backup Light for Trucks or Trailers - Submersible - Incandescent - Oval - Clear Lens part number BU70CB can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (190)
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Optronics Trailer Lights - BU70CB

  • Tail Lights
  • Oval
  • Incandescent Light
  • White
  • 6-1/2L x 2-1/4W Inch
  • Recessed Mount
  • Backup
  • Submersible Lights
  • Optronics

6-1/2" x 2-1/4" Oval. Waterproof incandescent light provides backup light function for trucks or trailers. Shock proof socket protects bulb. Recessed mount with grommet (sold separately). Accepts standard 2-prong plug.


  • Oval backup light for trailers and utility trucks
  • Sonically sealed, waterproof housing and lens unit is submersible
  • Shock proof socket protects incandescent bulb
  • Incandescent bulb can be easily replaced
  • Durable polycarbonate housing and lens
  • Clear lens covers incandescent bulb
  • Compatible with 12V DC systems
  • Recessed mount with grommet (A70GB - sold separately)
  • Accepts industry standard 2-prong plug (A45CB or A49PB - sold separately)


  • Dimensions: 6-1/2" long x 2-1/4" tall x 2-3/8" thick
  • Bulb type: incandescent
  • Power draw at 12.8V: 0.4 amps
  • 3-Year warranty

Manufacturer Cross Reference
Light will work as an exact replacement for:
Uni Bond # SE2238W
Wesbar # 203526
Truck Lite # 60204/60284
Grote # 62521
Peterson # M416
Bargman # 40-06-003

Optronics BU70 Series Sealed Back-Up Light Dimensions

Sonically Sealed, Waterproof Trailer Light

The waterproof construction of this light makes it ideal for use on trailers that may be submerged, like a boat trailer. The housing and lens are sonically sealed together to create a single unit, which means that water will not get into the light and damage the diodes or circuit board.

BU70CB Optronics Backup Light for Trucks or Trailers - Submersible - Incandescent - Oval - Clear Lens

Alternate part number: BU-70CB

California residents: click here

Customer Satisfaction Score:

Customer Reviews

Optronics Backup Light for Trucks or Trailers - Submersible - Incandescent - Oval - Clear Lens - BU70CB

Average Customer Rating:  4.8 out of 5 stars   (190 Customer Reviews)

6-1/2" x 2-1/4" Oval. Waterproof incandescent light provides backup light function for trucks or trailers. Shock proof socket protects bulb. Recessed mount with grommet (sold separately). Accepts standard 2-prong plug.


The light has no apparent mounting method. No screw or bolt holes. Can’t drill mounting holes without removing the lens, which appears to be unremovable.Makes sense, it’s watertight. No instructions at all.

My previous purchases at strainer have always been satisfactory, at the very least. I’ll have to return this one.

Jenny N.


This light is a recessed light that is meant to be installed into a pre-existing hole using a grommet part # a70gb. To wire it in you can use plug part # A45CB or plug part # A49PB. If this is not the type of light that you are looking for then I am happy to look for one that does. Would you be able to send me a picture of the light that you are replacing.



Jenny, attached is a photo of the trailer lamp that I’m trying to replace. Actually, I only need the lens, the rest of the lamp is ok. I had purchased a matching lamp from eTrailer several years ago but couldn’t locate it in your inventory. I’m happy to purchase the whole lamp and remove the lens. If you can help with that, I would appreciate

Jenny N.


Thank you for the picture. Based on the picture it looks like you have like part # RVPLL13AB which has an on and off switch at the bottom with an amber lens. I could not tell if yours had a switch or not. If this is your light then part # APLL11AB would be the replacement lens. In your order history you had ordered part # RVPLL13CB from us which has a clear lens a few years ago. The replacement lens for that clear light would be part # OPT47FR.



@JennyN Jenny, attached is a photo of the trailer lamp that I’m trying to replace. Actually, I only need the lens, the rest of the lamp is ok. I had purchased a matching lamp from eTrailer several years ago but couldn’t locate it in your inventory. I’m happy to purchase the whole lamp and remove the lens. If you can help with that, I would appreciate it.


Buy these they are water resistant. Don’t buy the junk on Amazon! You should use e trailer for all your lighting needs!


It got here so quickly!! It plugged right in and works just fine. Since I know its all good, I'm going to order another for the other side!


Great to find replacement lighting for 16yr old trailer. Simple installation, very good pricing. It works!!! Overall easy to find, order & install.

Tony C.


It still works and fits like the original. I now keep a spare. I have used etrailer for several trailertowing parts now and the professional knowledge and service are top-notch!


I'm highly impressed with these lights. I had one of the original amber Triton insignia running lights go out on my 2009 bass boat. Upon searching for a replacement I found these white lights could be used also in its place. After putting my order in, the lights arrived a day earlier than projected, came nicely packaged, AND the electrical connections came pre greased with dielectric grease. Very simple plug and play installation. THESE THINGS ARE BRIGHT!


Fit well. On the boat trailer. Sealed well. I would purchase again


The light fit perfectly on my rear ranch hand bumper, and the package arrived in a timely manner. Quick and easy fix!


Arrived sooner than expected, plugged rignt in, and works like a champ. I can acthally see what's behind me when I back up now.


Great service excelent price exact replacement
Product met my expectations product as advertised
from happy custumer


The light fit perfectly! It was exactly like the original that came on the boat trailer which needed to be replaced. Very easy to replace.


Light was well made and fit perfectly.


clear sealed backup lights were a perfect fit and work great at a great price with free shipping. I will use you guys again.

Jake C.


Good to go.


The light has held up and works as should on my boat trailer which is backed into the water several times a week.


Back up lights are a direct replacement for my trailer lights. Lights are much brighter than the original lights were.

George W.


Product is working great after a year.


I've purchased 4 replacement lights for my boat trailer, shopping on their website was easy, shipping was quick and the products worked great!



the lights are still burning bright!


Very tight fit for dock lights on motorhome. Had to trim fiberglass to fit. Electrical Connection is exact match.



Great very pleased with this item


Lights work as desired.

Customer Service.
Repeat Buyer.


I'm glad to find this website. One of my backup lights on my Ranchhand bumper went out. I couldn't find a replacement locally, so I began searching the internet. Found and the replacement bulb. Ordered the light and it arrived on time. I have this site bookmarked now and will use it again.


I recently bought a 2004 horse trailer. Overall, the trailer was in fabulous condition, except for the tail and marker lights which had been faded by overexposure to the sun for ten years. I ordered replacements for all the lights on the trailer and was very pleased with the speed of their arrival and the ease of replacing them. Now my trailer looks like new. Thanks E-trailer.


First of all I want to thank etrailer for being in business, I had looked all around trying to find the backup lights for my trailer. I found etrailer on the web and the rest is history, web site is easy to navigate, good product description, good pricing and items were in stock and shipped the same day I ordered, I got quick responses from etrailer reguarding my order and shipping details, I used regular shipping and received my order 1 week from the day I ordered, I will be telling my friends about etrailer and I will order from etrailer for my next trailer needs in stead of spending my time shopping around.


Product was just as shown & described on the site, great service and prompt delivery, will order from etrailer again, Thanks to everyone involved in getting my order to me

Mike G.


Great, no problems


Exactly what I needed for custom flatbed on my truck. Can't get locally. Re-used previous rubber seal from old light. Slipped in fine. Even had dielectric gel on contact points. Thanks for quick shipping and easy ordering. Will buy more replacement lights from you in future.


Bought a set of these to replace the old yellowed docking lights on my motorhome. Fit perfectly, work great.



The lights still look and operate like new, Im very happy with them.


The light is working fine after a year of use. Water is above the light every time I launch my boat. I have had no problem at all. It was easy to install. When I ordered the light I received it right away. The price was good and the service was great. I will use etrailer for parts whenever possible for future orders.


I purchased a docking light for our RV from The ordering process was hassle free and the product shipped super quick. The light was a perfect match. Ordering through was such an easy process - I plan to order extra lights to have on hand.

Show More Reviews

See what our Experts say about this Optronics Trailer Lights

  • How Much Power Does Optronics Backup Light # BU70CB Use
    The Optronics backup light # BU70CB is rated at 0.4 amps power draw at 12.8 volts. Wattage isn't something that is calculated for trailer lights since they are not tested for their rates of energy conversion. I have included a link to a video review of this light for you.
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  • Replacement Reverse Light for 2007 Forest River Lexington Motorhome
    The best option we have to replace the reverse light on a 2007 Forest River Lexington Motorhome is with the ONE LED Backup Light part # BUL003CB which has roughly the same overall size and uses the same three prong connector.
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  • Will Optronics Trailer Back Up Light Work With 2-Wire Pigtail
    I called my contact at Optronics and asked about the pigtail that can be used with the Oval Trailer Back Up Light, part # BU70CB. I was puzzled by the notes that say you can use the 2-wire pigtail, part # A45CB since the light has a 3-wire plug on the back. My contact said that on the BU70CB, the third plug is a dummy and is not used on this light. The A45CB will plug into two of the plugs and work just fine without compromising the waterproof seal.
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  • Replacement Interior Lamp for 2008 Exiss Sport Horse Trailer
    Your existing lamp is an Optronics # BU70CB. The lamp is sealed, so the actual bulb inside is inaccessible. If the bulb burns out, you'd need to replace the entire lamp assembly, part # BU70CB. Because this lamp is rated as a reverse light for when the trailer is backing up, the DOT limits its brightness, and because it's an incandescent lamp it'll have a rather limited lifespan. I'd suggest going with an LED utility lamp like part # BUL72CB. You'd get a lamp that's the same dimensions,...
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  • Does The Optronics Trailer Light, # BU70CB, Have A Plug-In Wire Attached
    The Optronics Trailer Light, # BU70CB, does not have a plug-in wire attached. It will require the Optronics Straight 2-Wire Pigtail, # A45CB. This part is the 2-prong plug that inserts into the back of the light and has a 6 inch lead with two wires. The red wire is bare at the end and the white ground wire has a ring terminal on the end. You will also need the Optronics Rubber Grommet, # A70GB, for flush mounting the trailer light.
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  • Finding Clear Trailer Light to Replace SAE R 97 DOT
    The SAE number isn't typically a great way to track down replacement lights as it's not a part number so I don't know exactly what light you are looking for but the Optronics light part # BU70CB that you referenced is a clear light that is DC powered. You would need a grommet part # A70GB to mount it and then also the 2 prong wiring harness # A45CB.
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  • Can the BU70CB Light Replace a ST70RB and Be Used as a Reverse Light
    The # BU70CB is basically the exact same light assembly as the # ST70RB that you currently have on your trailer so physically it will install very easily and in the exact same way as the # ST70RB. To wire it up so that it illuminates when your vehicle is put in reverse would mean that you would need to run a wire from those assemblies to a reverse light circuit on the trailer connector on your trailer. Since you have a 2014 Ram 2500 you will have a 7-way connector, the center pin of your...
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  • Replacement Clear 6-1/2 inch Long Clear Trailer Light
    Sounds like you have something like the part # BU70CB or the # BUL22CB as they are both 6-1/2 inch long 2-1/4 inch wide clear lights that mount in a grommet and use a 3 prong style connector like part # A45CB.
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  • Wiring Plug Recommendation for the 6-1/2 inch Oval Light part # BU70CB
    I checked with Optronics and they recommend the part # A45CB and part # A49PB for plugs to fit the 6-1/2 inch Oval Light part # BU70CB that you referenced. It could be that your # A45CB just isn't orientated correctly so that it installs correctly, or that you are trying to install the plug into the wrong pins.
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  • LED Side Marker Lights to Replace Truck-Lite Model 60s on a Pumper Truck
    The LED side marker/turn signal light that is comparable to your Truck Lite model 60 is our Optronics LED lights part # STL78AB. It's 7-9/16 L x 3-5/16 W x 3/4 D. It's a flange mount as well as it is sealed, waterproof and corrosion resistant. Your current marker light, such as part # BU70CB, is 6-1/2 L x 2-1/4 W x 2-3/8 D. You may also be interested in the Optronics chrome accent ring, part # A78CB, to add a little quick and easy dress up to the lights and your Pumper. I included a video...
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  • How to Wire Up a Boat Trailer with a Reverse Light on a Vehicle with a 4-Way Connector
    I have a solution for you, but electricity and water do not mix well so you will want to unplug the trailer wiring harness before you submerge the trailer in the water. The best setup I can recommend that will accomplish your needs and will still allow your wife's vehicle with a 4-way to connect to the trailer would be a 5-way setup. To convert the 4-way on your Jeep to a 5-way all you will need is the # 20036. Basically this will plug into the 4-way of your Jeep and the extra wire will...
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  • Is the LED Oval Trailer Utility Light Brighter than the Incandescent Oval Trailer Back Up Light
    I went out to the warehouse and checked all of our clear oval lights. The Sealed, 6-1/2 inch LED Clear Oval Trailer Utility Light, 10 Diode, item # BUL72CB, whiter light than the light emitted by the incandescent Oval Trailer Back Up Light, item # BU70CB, but the light does not illuminate as large an area as well. The advantages of the LED light is that it does not draw near as much amperage as the incandescent light, it lasts much longer and it does not produce the heat produced by incandescent...
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  • How to Cut a Grommet Hole for Installation of the Oval Trailer Tail Lights # BU70CB
    The easiest way to cut the oval hole for the Rubber Grommet, # a70gb, to install the Optronics Light part # BU70CB, in my opinion, would be to use a Light Mounting Bracket for 6-1/2 inch Oval Trailer Lights, BK70BB, as a template and then use a hole saw the correct size to cut a hole on each end of the mounting location. Then, use a angle grinder with cut off wheel or a reciprocating saw with metal cutting blade to cut the straight top and bottom sides of the hole. The correct width for...
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  • Which Trailer Wiring Connector Has a Pin for Reverse Lights
    In order to add reverse lights to a trailer would would need to have a 7-Way on the trailer, like # 50-67-103, and a 7-Way on the vehicle. On the vehicle side, if you are looking at the back of the 7-Way where the wires connect, the reverse light circuit is the center pin. It will need to connect to a reverse light wire behind one of the vehicle tail lights. On the trailer side the matching pin is again the center pin. So from that pin, you would route wire to reverse lights. Reverse lights...
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  • Can a Trailer Backup Light be Wired to a Vehicle Trailer Connector
    Oval trailer backup light # BU70CB can be run directly off of the reverse light or 12 volt circuits from a trailer connector. If attached to the 12 volt circuit they would need to be put on a switch such as # PK34513. If wiring into the reverse light circuit they would turn on with the vehicle in reverse and turn off when the vehicle is shifted out of reverse. In either case you would not need a relay. If you wanted to mount the lights inside of a flat surface you can use grommet # a70gb....
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  • What is the Candela Output of Optronics 6-1/2 Inch Incandescent and LED Tail Lights?
    I do recommend you move to LED lights as they are going to last much longer than the incandescent lights on your horse trailer. As far as light output, Optronics generally measures their lights in candelas instead of lumens though at a distance of 1 foot candela is equal to lumens so you should have a good idea of how bright the lights are. I contacted Optronics and the representative was able to give me the candelas of each of the lights you were asking about. The incandescent # BU70CB...
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  • Reverse Light Wire Color on a 1996 Chevrolet K1500 Pickup to Allow Connection of Back Up Light
    The best way to confirm which wire activates your vehicle reverse lights is to remove one taillight assembly and visually identify which lead goes to the reverse light bulb. To remove the taillight, open the tailgate and locate and remove the two taillight retaining screws. This will allow you to pull out the taillight assembly for access to the wiring. Then, for safety sake, it will be useful to have a helper turn the ignition to the on position without starting the vehicle. Then place...
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  • How to Provide Power to Trailer Reverse Lights
    To connect back up lights you need to have a 7-way trailer connector on both your trailer and tow vehicle. On a 7-way the reverse lights are powered by the center pin. To connect reverse lights to the trailer's 7-way you can use 16 gauge wire # 16-1-1, or 14 gauge # DW07550-1 if you have a longer trailer. Both are sold by the foot. If you need reverse lights a couple of popular options are the Optronics LED Backup Light # BUL10CB for an LED that uses a 2-wire pigtail # A45CB to connect....
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  • Will Adding Optronics LED Backup Light to Kayak Trailer Require Rewiring the Trailer
    It sounds like you are wanting to replace your incandescent backup lights on your kayak trailer with LED lights like the Optronics LED Backup Light for Trucks or Trailers # BUL52CB. If that is the case, all you will need to do is replace the current lights with the LED lights. The # BUL52CB accept the industry standard 2-prong plug like the 2-Wire Pigtail for Optronics Backup and Utility Trailer Lights - 2-Prong PL-3 Plug # A45CB. If you do not have existing lights, then you will have...
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  • Replacement Tail Light for 1998 Jayco Travel Trailer
    Trailer manufacturers do not often maintain original parts information (or availability) for items such as lights, but we can certainly help you find a suitable replacement. You may want to just install a whole new light kit like # TL29BK or a high-efficiency LED kit # TLL9RK. This will avoid the same problem of no replacement part if the other light on your trailer should be damaged. Both kits include lights, a license plate bracket and all hardware. If you prefer to replace just the...
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Info for this part was:

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