This 10 inch Yellow Poly Vinyl Keel Roller Bracket Assembly will replace your rusted or worn keel roller on your boat trailer. Typically these are located along the center line of your boat trailer, this style keel roller makes launching and loading the boat much easier. We have put all the needed items together into a kit which does not come pre-assembled. This kit includes a 10 inch Yellow Poly Keel Roller, a 9 1/2 inch 5/8 inch diameter Zinc Plated Roller Shaft + Pal Nut Caps, a 10 inch Galvanized Roller Bracket along with Galvanized U Bolts and Galvanized Hardware to mount the assembly to a 2x3 Trailer Cross Member. You can view what this assembly will look like assembled by looking at the sample photo with this listing. This kit will either be an exact replacement for what is on your trailer, or you may be adding keel rollers to your trailer, or switching from a standard black roller to a nicer Polymer one like this. The purpose of this kit is to provide support, protection, and a more efficient method of loading and unloading your boat. Typically they will mount on your forward most cross member, and sometimes on your other cross members as well.