Features: Make of ABS and Stainless Steel, which durability and wear resistance and can used in salt water environment. The diving valves knob have a nonslip texture design, strong grip, nonslip and easy to use. Simple installation, not easy to fall off, it is a great replacement part for scubas diving cylinder valves. With clear switches direction marking, it intuitively prompts the rotation direction and effectively reduces the risk of operational errors. his scubas diving tanks valves knob is the key component for opening and closing your scubas tanks valves: simply turn counterclockwise to release gas or clockwise to seal the tanks. Specifications: Component: ABS and Stainless Steel Type: Long/Short Color: Yellow/Blue/Black/01 Size: about 2.5x5.2x3.8cm/0.98x2.05x1.5inch Package Includes: 1pc Cylinder Valves Handwheel Knob note: Please allow 1-2cm errors due to manual measurement, make surely that you not mind before order. Due to difference between different monitors, the picture may not reflect the actual color.