Dorsal Premium Surfboard 6, 7, 8, 9, 10 FT Surf Leash - Blue ProComp Big Wave Surfboard Leash DESIGN: Day-to-day performance and strength, the Blue Premium Comp Leash will perform to the highest standard in a wide range of conditions. FEATURES: Cord thickness: 7mm Wave size: 2 - 8 feet + Flat Water Interchangeable Smooth rotating nylon cuff and rail saver swivel assembly.