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Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole - White

Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole - White

Item # WHMAV2
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WHMAV2 - Wall Vent Redline Accessories and Parts
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This half-moon-shape vent forms the exterior part of the Alliance 2-piece enclosed trailer vent. Constructed of UV-resistant polypropylene plastic that holds up to sun exposure. White color. Call 800-298-8924 to order Redline accessories and parts part number WHMAV2 or order online at etrailer.com. Free expert support on all Redline products. Guaranteed Lowest Price and Fastest Shipping for Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole - White. Accessories and Parts reviews from real customers.
  • All Info
  • Reviews (7)
  • Q & A (3)
  • Videos (2)
  • Photos
  • Why etrailer?

Redline Accessories and Parts - WHMAV2

  • Enclosed Trailer Parts
  • Wall Vent
  • Redline

This half-moon-shape vent forms the exterior part of the Alliance 2-piece enclosed trailer vent. Constructed of UV-resistant polypropylene plastic that holds up to sun exposure. White color.


  • Exterior vent is the outside part of the Alliance 2-Piece Polypropylene Trailer Vent for 3" Diameter Hole
    • Fits round interior trailer vent (WAVT2; sold separately)
  • Half-moon piece with flat, slotted side attaches to trailer's exterior
    • Slots are on one side only, allowing you to position the vent for best airflow and to help prevent water from getting in
    • Drain holes at the corners let out any water that does get in
  • UV-resistant, polypropylene plastic construction stands up to the elements
  • White color
  • Overall dimensions: 8" long x 6" wide x 1-1/4" tall
  • Flange width: 1/2"
  • 6 Screws (sold separately) required for installation
    • Hole diameter: 3/16" (fits #8 screw)
  • Sealant sold separately

WHMAV2 Alliance Outside Half of 2-Piece Enclosed Trailer Vent - UV Resistant Polypropylene Plastic - White

Video of Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole - White

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Redline 2-Piece Polypropylene Trailer Vent Review and Installation

Jake: Hey guys, it's Jake here with etrailer. Today we're going to be taking a look at the Redline half-moon trailer vent. This is going to allow fresh air to get in and hot air to get out without having to worry about getting any water inside your trailer.In this kit, you are going to get the outside vent and the inside receiver so that you can have a nice clean look on the inside of your trailer. This is really going to be important for if you have a wall inside your trailer like we do, but if you don't have a wall, you can just use this part and you'll be able to mount it to the outside of your trailer and get fresh air without having to worry about any water.So you can buy these as a kit or you can buy them separately. Now here you'll see we have our vent in black. It's also available in white if you'd like to match it to your white trailer.Here's that piece on the inside wall that we we're talking about.

This is going to give it a nice clean look so you just don't have an open hole in your wall. It's going to have a nice flush mount design so you don't have to worry about anything running into it when it's on the wall. It's also going to help preserve this part from being damaged.If you want more of a cross-flow to go into your trailer, you could pick up a couple of these vents to be able to put one on the opposite corner of your trailer so that you have wind coming in the front and going out the back. When using two vents, it's going to provide a way for cool air to get in and warm air to get out. Now that we've gone over some of those features, let's go ahead and show you how we got it installed.We'll start by drilling a 3" hole.

We're going to start on the inside so that we know we're not going to run into anything inside the walls. You can see we have our ribs here and here, so we're going to split the difference and do it in the middle of them. Then we're going to continue with the hole saw through the sheet metal on the outside so we know where our hole needs to be drilled. We'll go ahead and insert our pilot bit into the hole that we punctured through the sheet metal and start drilling out our hole.I'm going to go ahead and insert our vent on the inside and fasten it down. Here we just found some stainless steel screws so we don't have to worry about any rust.

Now we can move to the outside, and we can go ahead and get our outside vent in place, slide it over. We'll use a self-tapping screw, but you want to be careful with this sheet metal on the outside of your trailer. It's not very thick. You don't want to strip it out. We'll stop right there and hand-tighten from here.

Now we'll go ahead and get the other five screws in place.Now, we went ahead and put some of this Loctite black silicon gasket on the inside. We took our cover off and put it on the inside to seal it up nice and neat to make it a nice watertight seal. We do have this at etrailer. You can pick some up if you'd like.Once you have all your screws in place, you're ready to hit the road.With all that being said, that's going to do it for our look and installation of the Redline half-moon trailer vent.

Customer Reviews

Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole - White - WHMAV2

Average Customer Rating:  5.0 out of 5 stars   (7 Customer Reviews)

This half-moon-shape vent forms the exterior part of the Alliance 2-piece enclosed trailer vent. Constructed of UV-resistant polypropylene plastic that holds up to sun exposure. White color.


Arrived exactly as described and on time. Customer service is second to none. Every purchase I've made has been handled with courtesy; every question answered thoroughly and correctly 756600


It's great having a company that stocks trailer parts like these. Had a blowout on my trailer, tire took vent off. Exact match!!! Thanks!!! 706201


Very satisfied with the purchases. All installed and functioning well. 312869


Product as described . Install yesterday on my sprinter van. Although white in color turns into a oven during the day . so I installed the vents up high on the back side corners. when I leave a job and vehicle is hot inside I crack the front windows and the vents naturally vacuum the hot air out , until the AC catches up. Thanks , happy with product and as described. 264188


Product came as advertised, on-time in good condition. 210074


Great company to work with and great service too! 189214


Exact replacement for the vent cover on my trailer. Same shape/holes, etc. Saved time and money. Just remove the broken cover and install the new one. 126155


Ask the Experts about this Redline Accessories and Parts

  • Is There Recommended Hardware to Install Half-Moon Vent on a Fiberglass Box Truck
    Since vents like the Replacement Exterior Half-Moon Trailer Vent # WHMAV2 are for a universal application we don't really have recommended hardware as each installation will be different. From what I could find online it looked like steel screws would be best and you would want to drill into the fiberglass first and then put some sealant like part # 0160297 on the threads of the screws before installing them. I would do some research on your end of things and maybe contact the manufacturer...
    view full answer...
  • Availaiblity of White Half Moon Trailer Vent
    We do have the white Replacement Exterior Half-Moon Trailer Vent for 3" Diameter Hole # WHMAV2 which is the white version of the # HMAV2 that you referenced and also is what you sent in a picture of so it would work well for you.
    view full answer...
  • How To Install the Redline Trailer Vent # WHMAV2-WAVT2 on an Enclosed Trailer
    I do not have an installation video on the Redline Trailer Vent, part # WHMAV2-WAVT2, but I can help you with the installation. The tools you will need are a caulk gun, drill, a 3-inch hole saw, a 3/16-inch drill bit, and a flat-tip screwdriver. The other parts you will need I have listed below in the instructions. The # WHMAV2-WAVT2 vent is two pieces. The # WAVT2 is the 3 inch round interior vent that will need to be installed in a 3 inch diameter hole on your trailer. You will need...
    view full answer...

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Info for this part was:

Written by:
Raymond P
Video Edited:
Chris R

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