Cantilever Gate Wheels Cantilever Slide Gates Cantilever Gate Rollers 1 Wheel with cover External Roller Assembly A graphite-impregnated Nylon wheel to reduce the effective drag Mounting Hardware an integral part of the Cantilever Gate Roller System Quality Assurance Gate opening size up to 30 feet Load Rating  4000# reaction load Warranty: Manufacturers limited lifetime warranty against defects in materials and workmanship Nylon Dust Covers  protect the bearings on each side of the wheel.