At the end of the lawn mower season if your lawmnower has a shut-off valve on the fuel line, turn off the valve and run the engine until it quits. This will assure all the fuel is used up in the carburetor before storing.If the lawnmower has no shut off valve on the fuel line, consider installing one, otherwise drain the tank and run the engine until it uses all the fuel before storing.Also use a shut off valve as a safety feature during the season when storing equipment in a garage or storage building between mowings. It helps with fuel leaks due to a bad needle valve or leaking carburetor.Fuel Shut Off Valve For 1/4 inch Fuel LineRepalcement manufacturer part number: 494768,493960,698183,698181,697947,5019H,5019KReplaces 494768, 698183, 698183MA, MU698183Replaces for 1-603770, 54-3150Replaces for Murray, Snapper 7034212YP, 7034212Replaces for John Deere AM107340 AM36141Color: Black + redMaterial: ABSPackage Contents:30 pcs * fuel shut off valve60 pcs * clampsOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.