Specially compounded cover is soft and extremely flexible at sub-freezing temperatures. It also resists damage from weather, fungus, atmospheric pollution, and abrasion. Patented 8-layer construction featuring 2 layers of polyester cord reinforcement withstands hose nozzle shutoffs and pressure twists. Black Flow Guard Plus collar prevents kinks near faucet. Octagon brass coupling are crush-resistant. Do it Best Flexogen floats and has a 500 psi (pounds per square inch) burst strength.