Valve Core Removal Tool. Remove and replace valve cores without losing the system's refrigerant charge with Uniweld's valve core removal tool. Now you can temporarily remove valve cores for unrestricted line flow, providing faster recovery, evacuation and recharge of a system. The 3/8" full flow ball valve, with positive 1/4 turn on/off, swivels 360º for easy access to system service valves. Attach vacuum gauge at the system for faster vacuum with the valve core removed, using the optional side port adaptor.