Scuba diving threaded dust plug protector for DIN valves work with either 200-bar or 300-bar DIN valve fittings With swivel attachment lanyard Lightweight, strong, portable and saltwater resistant The plug is vented so that the presence of high-pressure gas does not trap the plug and makes it difficult to remove Great replacement accessories for underwater scuba diving din first stage regulator Specification: Material: ABS Color: Black Height: Approx. 2.8 cm/1. Outer Diameter: Approx. 2.7 cm/1.06 inch Thread Inner Diameter: Approx. 2.18 cm/0.86 inch Size Chart: Height: Approx. 2.8 cm/1. Outer Diameter: Approx. 2.7 cm/1.06 inch Thread Inner Diameter: Approx. 2.18 cm/0.86 inch Package Includes: 1 Piece DIN Tank Valve Dust Plug(50 Pack) : Please allow slightly difference due to manual measurement. Color may be slightly different since different monitor. Thanks!