PRICES MAY VARY. Compatible with all OPD/QCC1 valves, these are suitable for 4 - 40 lb. cylinders used in gas BBQ grills, generators, portable heaters, and other applications. A 10-inch chain tether ensures the valve plug remains attached to the tank, preventing the loss of plugs. Prevents dirt, dust, water, and insects from entering the valve. Left Handed Thread MADE IN THE USA! Includes Red Silicone O-Ring Threaded Plugs with 10-inch Chain Tethers are designed for 20-pound LP Gas Grill tanks. Portable Heater, Gas Bbq, Bbq Grills, Camping Stove, Generators, Bbq Grill, Propane, Gas Grill, Left Handed