This is a Galvanized Winch Post Stand for Boat Trailers with 3 inch Wide Trailer Tongues. This means that the mounting base of this winch post is designed to rest on the trailer tongue, and be U Bolted in place. This particular model is made with 2 x 3 galvanized 11 gauge steel. The base and support are welded to the tubing to create a strong finished winch post stand. This is the 28 inch Model. To view exact dimensions to help you select the correct winch stand, take a look at the pictures of this product above, you will see detailed measurements drawn on the image for reference. The main beam of this stand measures 28 inches. You can use the measurement photos to match this up. You will mount this stand to your trailer tongue using (2) of the correct 3/8" or 1/2" diameter U Bolts that are 3 inches ( 3 1/16") Wide. The Length of the U Bolt used depends upon the height of your trailer tongue. Most 3 inch wide trailer tongues are 3 to 4 inches tall, this would be very standard. For 3 x 3 Tongues, use 1/2 x 3 x 4 5/16, for 3 x 4 Tongues, use 1/2 x 3 x 5 5/16. In addition to the U Bolts, you would use (2) 3" Wide Shackle Plates to secure the U Bolts around the Winch Post Stand and tongue. The Correct Shackle would be Leaf Spring Shackle Galvanized 3 1/2 inch Long. This Shackle measures 3 1/2" Center to Center Hole, which makes between hole measurement 3 inches. With this Shackle, you would use a 1/2" Diameter U bolt, as the holes drilled in this shackle are also 1/2 inch. This would mean (2) U Bolts, and (2) Shackles, to mount this winch Stand to your Trailers tongue.
Most Winch Post Assemblies are made up of two pieces, a post, and a support. They will U bolt together to create a mounting service for your trailers winch. The easiest way to select a Winch Post is of course to get an exact replacements. However, in many cases an exact replacement is not available, maybe the company is out of business, or the product has been discontinued. If this is the case, try and compare measurements to find the closest replacement available.
To Mount a Winch Support to this post, the support would need to be able to have mounting holes positioned to mount to a 2 inch Wide Winch Post, which is what this listing is for. So verify the hole spaces on the Winch Support, to make sure it will mount to a 2 inch wide post.