Fulton Roller Guides - Fulton Boat Guides enable you to visually guide your boat onto your trailer. The easy-to-use design is easy to install, and is adjustable to accommodate any hull design. Manufactured in non-marking, marine grade PVC, the Fulton Boat Guide features easy clamp-on installation with no drilling required. High-strength, super-grip mounting brackets attach above and below trailer frame. For trailer frames up to 3" x 5". Made in USA. Easy-to-use designFor trailer frames up to 3" x 5".Non-marking, marine grade PVCMade in USA