We will provide comprehensive quality assurance for our product. When turning the key, the cam will touch the side wall of the filler neck and bite ( Please note that there is no need to overtighten the cap ) -Super high quality can prevent corrosion and rust and long service life., -Easy to operation. Aazon.co: Locking Diesel Fuel Cap Copatible with Freightliner... Truck Cap 2 3/8" Locking Diesel Fuel Cap Compatible With 2002 And Up Freightliner... Peterbilt Fuel Cap It fits perfectly onto your diesel tank and gives you peace of mind. l 【INCLUDING】 Our diesel gas cap comes complete with two keys, a security chain and a hanging ring, as well as a rubber sealing ring for extra protection 【FITS】Compatible with 2002 and Up Freightliner M2 Small Semi Box Trucks (Fuel Tank Must be Vented), Replace# FTA-C-13., And the operation is very simple. 【PREMIUM QUALITY】Long life-span matters, that is why our truck lock tank cap is composed of heavy duty aluminum, which can effectively prevent corrosion and rust, greatly increase the service life even in rainstorm or high temperature environment. It fits perfectly onto your diesel tank and gives you peace of mind. 【12-MONTH WARRANTY】 If for any reason at all, you are not fully satisfied with lock cap, simply contact us through amazon message at any time. 【NEEDS】Say goodbye to worries about fuel theft or cross-contamination with our anti-theft fuel gas cap. Locking 2 3/8 Fuel Cap Diesel Fuel Cap Compatible Haiti ▶FUNCTION◀-The fuel caps provides a tight seal to keep your vehicle's fuel tank closed, safety your vehicle's occupants, fuel economy and reduce vapor emissions. Why you change this Locking Diesel Fuel Cap? -Preventing diesel theft.