Removes And Installs Valve Cores And Valve Core Caps. The double ended core driver reverses in the tool body. The reversible driver fits both large and small valve cores. Use the reverse end to remove and install valve core caps. The long tool handle will access inside dual wheels. The lightweight aluminum body is equipped with a pocket clip. 14110 Core Driver *driver has standard tip that is .175 dia. and .248 dia. on the other tip.