Best used a replacement block. The foam rack pads are best used in pairs. Get two if you are going to assemble your own foam block kayak transport system and supply your own straps. Foam block Kayak-SUP pads are 24x4x4 inches. Use on cross bars or directly on a plain roof top. Kayak-SUP foam rack blocks have a non-skid laminate bottom. The block is shaped to conform and cushion virtually any kayak hull shape. Slots in the block base fits round, square and factory oval cross rail systems.
Two of these, with some 1.5 Inch Web Strap Products can be used to make the discontinued Ocean Kayak Soft Racks.