[Package Includes] : 10 Sets 1/2" Impact Wrench Retainer Rings & O-ring + Anvil Tool [Compatible with]: Electric/Pneumatic Wrench, Including Retainer Ring Anvil Install Tool [1/2" Anvil Retaining Ring Install Instruction]： Step 1: Install new o-ring to your wrench. Step 2: Put retaining ring into install tool recess. Step 3: insert the anvil into the retaining ring with 45 thrust. Step 4: Push and bring the anvil perpendicular. [Note]： Specifically designed to fit Milwaukee type 1/2" cordless impact wrench. Does not fit DeWalt or other cordless tools. 1/2" Impact Wrench Retaining Ring with O-Ring Fit for Milwaukee Cordless Type Wrenches, Impact Hog Ring come with Anvil Retainier Ring Install Tool (10 Sets) [Good material]: The O-ring is made of high-quality rub ber, which is reliable and not easy to break The snap ring is made of carbon steel, which is sturdy and durable, wear-resistant, and has a long use time Includes anvil retaining ring installation tool for quick and easy installation