The Classic Army DT-4 Double Barrel is a tough beast that is able to fire a BB through two barrels. After thousands of shots, the piston may wear down depending on how much stress the DT-4 has gone through. Classic Army has got you covered with OEM replacement parts during the improbable event your piston strips! The metal teeth along with the aluminum body are able to hold up through rigorous use. Make sure you have the components you need to keep your Classic Army DT-4 running.90 with OEM parts!