Features include special, non-marking, "two compound" rollers, with durable wear resistant inner surface and soft boat cushioning outer surface. Two different D-L designs - original design attaches directly to vertical mounted 2x4 bunk board mounting bracket or can be mounted with optional bracket No. 6356. Rollers are free to pivot and align with boat hull, 2 rollers per set. Constructed of 14 gauge steel in black powder-coated finish; deluxe style universal mount attaches directly to either vertical or horizontal positioned bunk boards and features 3 rollers per set. Bracket 6389 optional. Constructed of 12 gauge pre-galvanized steel.