Ford/Motorcraft does not make an OEM gas cap for my 2016 F250 V-8. This aftermarket fits well and closes securely. Provides the tightness required for exhaust gases. Not reliable, but serves its purpose. In Southern California, where gas is $7 a gallon (March 2022), yes, it's a must. No, it won't stop the gremlins from piercing the tank or cutting the fuel line. But I'm not going to make it an easy siphon. Happy with the purchase.