The RS1200 kit adds rollers to the SD1200 and SDPONT kits. The extra roller sets include 2 rollers with brackets and fasteners. Includes 2 rollers, 2 brackets and hardware

The WSB kit is a pair of side braces with fasteners (used for strengthening rail beam to cross members). Add these kits when making your ramp longer than the standard SD1200, SD2000 and SDPONT kits. Includes 2 side braces and hardware.

The RS2000 kit adds rollers to the SD2000 kit. The extra roller sets include 2 double-roller axles, 4 rollers, brackets and fasteners. Includes 4 rollers, 2 tiltable axles and hardware.