Comprehensive Set: Includes 8 sets of 1/2inch and 8 sets of 3/8inch impact retaining ring clips, O-rings, and hog rings - a total of 16 sets. Compatible Tools: Compatible with electric and pneumatic impact wrenches, fits both 3/8inch and 1/2inch anvil sizes, ensuring versatility across various tools. Install & Use: How to Install New O-Ring: Place Retaining Ring Into Install Tool Recess, Insert Anvil Into Retaining Ring at a 45° Push and Bring the Anvil Perpendicular. Anvil installation, easy to install quickly, can reduce downtime. It is an indispensable tool accessory on the fixed equipment. The o-ring is made of high-quality rubber, which is not easy to break; Versatile Usage: Suitable for a wide range of projects and applications requiring impact wrench installation. Please note: the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour:Photo Color Material:Rubber+Iron Package Contents: 8sets x 3/8inch Impact Retaining Friction Ring Clip with O-Ring 8sets x 1/2inch Impact Retaining Friction Ring Clip with O-Ring 1pcs x Anvil Tool Only the above package content, other products are not included. Note: Light reflection 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.