The Self-Centering Style Roller is designed to assist you in loading the boat onto the trailer, to help give you that extra push and line up your boat.
Rollers in general are near essential to the loading in unloading process. Not only can they ease the process, but they also protect your boat from impacting the trailer at crucial points. Trailer Rollers are placed at important points on your boat trailers cross-member, typically along the center-line of the trailer. These rollers prevent damage to the boat and assist in support of the boats hull while trailering, loading, and unloading.
Typically, a keel roller mounts inside of a bracket, often referred to as a roller bracket. This roller would have a shaft running through its center, with caps, pins, or nuts holding it in place. This assembly is they bolted or u-bolted to the trailers cross-member. Seen in this listing is a picture of a Stoltz Poly Boat Trailer Roller
This is a solid Trailer Roller! Check out your arrangement, and the parts you will need to finish the project! Let us know if there is anything we can assist you with!