Non-skid laminate. SUP Carrier Kit: Includes: 2 Universal SUP/SOT Non-Skid Foam Blocks 2 SUP Stacker Blocks 2 9’ Block Straps 2 15’ Center Straps with Cam Buckle. SUP/SOT Universal Block: 3.75in H x 4.75in D x 31.5in W. SUP Stacker Block: 1.25in H x 4.75in D x 23.25in W.