Recessed flush straps, Resilient, absorbs impact, Retains shape, Cover tight with Grid. Finest Materials, Spike Proof Cover, Vinyl Cover, Waterproof and Washable. Best buy for money Nylon straps long wear permanently white. Features: - 15" x 15" x 21/2" slide over safety base for all skill levels., - Modular one piece all rubber construction., - Tapered sides., - Heavy gauge non-collapsible textured white rubber., - Aluminum stanchion fits both male and female ground anchor.,