GREAT FUNCTION -- The valve core remover installer tool is made of solid brass. The metal knob is all designed with anti-slip design; The core tool be easily inserted into the inner valve core to control the core. No need to stop the machine, no need to release the refrigerant. APPLICATION -- Work with Schrader, , Dill valve core remover installer changer R22, R410a refrigeration air condition .The dual size 1/4&5/16 can adapt to R22/R134/R410/R32R air-condition. HIGH QUALITY -- High strength and hardness. Designed with a stainless steel ball and brazed side fitting for durability and . Remove valve cores quickly and easily. GOOD DESIGN -- , solid brass tool has a ball valve that can be opened and closed in just a quarter-turn, rather than a slower to operate stem-type valve. (No Gas Loss) EASY TO USE -- The core tool be easily inserted into the inner valve core to control the core. Please close the valve and disconnect the air conditioner before removing the valve core. How to Remove Old Valve Core: Connect and lock the valve core installer to your home A/C valve core screw port. Please choose whether to add 1/2 inch pure brass adapter according to the actual situation. Turn Disconnect valve to vertical position, insert Valve core remover rod, slowly rotate to find and insert your home A/C valve core. Rotate Valve core remover rod counterclockwise. After hearing the sound of "Puff...", rotate counterclockwise 3-5 turns to remove your valve core, and then pull out Valve core remover rod . Turn Disconnect valve to horizontal position, unscrew Extremity port unscrew , take out Valve core remover rod , remove your broken/ old A/C valve core. : Colour:yellow Material:brass Package Contents: 1 x 1/4 inch and 5/16 inchValve Core Remover 4 x Valve cores Note: Before removing the valve core, close the valve core wrench valve and disconnect the air conditioner internal connection. Small parts, keep away from children. Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.