The Matco Tools Fuel Tank Locking Ring Wrench, No. MST6599A, is designed to remove and install fuel tank lock rings when servicing fuel pumps or fuel sending units. The device fits on a variety of makes and models of fuel tank lock rings, is made from hardened steel, and is designed to work with 1/2" drive ratches and breaker bars. The product weighs 1.25 lbs.