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ThinLine Mini LED Side Marker or Clearance Light w/ Bracket - Submersible - 3 DIodes - Amber Lens

ThinLine Mini LED Side Marker or Clearance Light w/ Bracket - Submersible - 3 DIodes - Amber Lens

Item # MCL-91AK
Our Price: $12.46
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Trailer Lights
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Shipping Weight: 0.13 lbs
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2-1/2" x 1-3/16". Waterproof mini trailer light functions as a clearance light or side marker light when properly mounted. Durable polycarbonate lens. Surface mount with self-grounding bracket and hardware. 1-Wire design. P2 rated. Great Prices for the best trailer lights from Optronics. ThinLine Mini LED Side Marker or Clearance Light w/ Bracket - Submersible - 3 DIodes - Amber Lens part number MCL-91AK can be ordered online at or call 1-800-940-8924 for expert service.
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Optronics Trailer Lights - MCL-91AK

  • Clearance Lights
  • Rectangle
  • LED Light
  • Amber
  • 2-1/2L x 1W Inch
  • Surface Mount
  • Rear Clearance
  • Side Marker
  • Submersible Lights
  • Optronics

2-1/2" x 1-3/16". Waterproof mini trailer light functions as a clearance light or side marker light when properly mounted. Durable polycarbonate lens. Surface mount with self-grounding bracket and hardware. 1-Wire design. P2 rated.


  • Small, rectangular trailer light functions as a clearance light or side marker light when properly mounted
  • Sonically sealed, waterproof housing and lens unit is submersible
  • LEDs make great replacements for incandescent lights
    • Last 50 times longer
    • More efficient - provide brighter light with less power output
    • No bulbs to replace - no brittle filaments
  • Durable polycarbonate lens and housing
  • Amber lens over white LEDs
  • Surface mount with self-grounding bracket - hardware included
  • Single wire design grounds through mounting hardware
  • P2 rated


  • Dimensions: 2-1/2" wide x 1-3/16" tall x 7/8" deep
    • Dimensions with bracket: 2-7/8" long x 1-1/2" wide x 1-1/4" deep
  • Distance between mounting holes (center on center): 2"
  • Diodes: 3
  • Power draw at 12.8V: 0.051 amps
  • Lifetime warranty on LEDs

Optronics MCL91 Series ThinLine Side Marker and Clearance Light Diagram

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.

P2-Rated Lights

Diagram of light spread for P2 rated light

A P2-rated light produces a 45-degree angle of light to either side of its centerline for a total of 90 degrees of coverage. This beam pattern can be seen straight on, but it cannot be seen clearly from the side. So this type of light can be used as either a side marker light or a clearance light, but it cannot function as both. If you need both functions, then you must install 2 separate lights on your trailer - one as a front or rear clearance light and one as a side marker light.

MCL91AK Optronics Thin Line Mini LED Side Marker and Clearance Light with Bracket - Submersible - 3 DIodes - Amber Lens

Alternate part number: MCL-91AK

California residents: click here

Customer Satisfaction Score:

Customer Reviews

ThinLine Mini LED Side Marker or Clearance Light w/ Bracket - Submersible - 3 DIodes - Amber Lens - MCL-91AK

Average Customer Rating:  4.9 out of 5 stars   (1412 Customer Reviews)

2-1/2" x 1-3/16". Waterproof mini trailer light functions as a clearance light or side marker light when properly mounted. Durable polycarbonate lens. Surface mount with self-grounding bracket and hardware. 1-Wire design. P2 rated.


Nice to have a wide range of marker lights to choose from. Ordered the LED marker along with a new fender. They even upgraded my shipping at no extra cost!


It works great as all Optronics lights I have purchased.


Easy to install. Its bright, lights up the side of my trailer very well.


Great LED lights very bright


Found everything i was looking for, easy ordering, prompt shipping, and quality products, enough said


The product performed as expected. It was easy to install and worked out of the box.
I was looking for a light that would provide a bright light and not consume a large amount of electrical current. These lights were installed on a boat trailer and I wanted something I did not have to worry about getting submerged when on.
They work great.

Lights are still working great.
Barry W - 10/17/2017


Fast service and exact fit. Thanks


These lights are well made and look great. They are a direct replacement for the older version I have. Tinted them to match the trailer. They were very easy to tint as the light surface is very flat.


The lights work, BUT i had a major issue with the design.
The wire that provides 12V to the light has the potential to ground against the frame and documentation makes no mention of this. i blew every fuse in my truck because of this light direct shorting to frame ground and couldnt figure it out at first. upon taping the connection and replacing fuse it became clear. BE CAREFUL on how you install these connectors! a rather poor design to have so much wire sticking out of the back that can contact trailer frame! (having said that you tape them up right they work just fine.)


Very happy with the lights I purchased. Being LED they are quit a bit brighter then the old ones that came with the trailer. Was very happy with Etrailer in the quality of the product and the quick turn around.

No problem with the lights. I have been very pleased with the product and company. Would suggest doing business with etrailer.
Rick B - 02/05/2018


Matches original exactly.


The LED lights are very good - very bright - but the mounting hardware to fit on a plastic boat fender is far from satisfactory. Two screws came with the lights which just won't work on pre-drilled holes from the previous lights. So a trip to the hardware store was my next step to purchase nuts, bolts and washers.


Bought a brand new trailer and from the get go some of the regular lights were intermittent. Finally had enough and ordered LED's to replace them all; have not had a single light issue over a year later. All were direct drop in replacements, fit and look great. Thanks!


I love the LED lights!! They give me a brighter lighting around the trailer assisting me in attaching tie downs at night, I can clearly see the corners on my trailer while backing up. They look great and fit nicely on the my trailer.
Extremely pleased with and this product.


These lights are still working flawlessly after one year of use. etrailer sells great products and their customer service is awesome !!!

After 2 years these lights are still working without issue. Recommend this products!!
Scott R - 05/18/2018


The lights are excellent, a direct replacement. i ordered lights with the chrome frames but not really thinking I would actually use the frames, however trying to get the old lights out required either breaking them or the old plastic frames. Only 4 stars because the new frames require drilling new holes. I went through many websites and even yours I wasn't completely sure I was getting the right lights until they arrived.


Replacing incandescent for LEDs, on my boat trailer. I liked the chrome housing, same as my old ones. Have yet to put them on, will update review after that.

Put them on finally, workslooks better than expected! Lights are soooooo much brighter than the old ones! Fantastic product!
Swisher 1 - 04/25/2014


These lights where bought as replacements for the same lights I bought 11 years ago. They go on the running boards of my Ford F250. 3 had gone dim so I replaced all 6 and these where exactly like the originals. Easy install and they are bright. Hope I get 11 more years out of these.


This replacement trailer light was spot on. Will definitely use this company again!


The product is exactly what I ordered.
only question is;

My application is a surface mount? The wiring will need to be external of the bezel. If it were notched to allow this it would complete my application.

Thanks for your interest after the sale.

The LED Markers are excellent. Bright and low voltage, just what I needed.The center BrakeStop light still is not installed. I live in a retirement community with lots of electronic experience and we cant figure it out. It will bench test but will not work with my golf cart wiring??? We think it is a ground problem that could be resolved with a new harness....but I would have to give up a day of golf ...choices choices choices.Thanks for your continued interest and I promise the next rainy day we will run a new harness.Ed McNamara
Ed M - 10/18/2014


Good quality lights, just be sure to drill the hole for the power wire over size so that the power port on the back of the light doesn't ground out on the trailer frame.


Didn't like desing of lights.


Great product snapped right into my existing frame. If I were to mount the light the mounting holes are on the small side. My existing holes are 1/4" and these are smaller. Not an issue just need a button head bolt and nut on the back for replacement. Very bright look great.


Great product. Had an issue with one of four...contacted etrailer and they supplied a replacement without issue. Can't say enough good things about this company. Thanks!


Easy install, works perfectly. Much more visible than the old lights.

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Employee Jameson C
Expert Research:
Jameson C
Employee Cole B
Installed by:
Cole B
Employee Wilson B
Updated by:
Wilson B
Employee Brian T
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