Astro 1812-3132 Anvil O-Ring and Retaining Ring, 10-Piece Compatible with any Astro Pneumatic 1/2" Standard Impact Compatible with any Ingersoll Rand 1/2" Standard Impact Wrench Compatible with any Chicago Pneumatic 1/2" Standard Impact Wrench Compatible with any Matco Tools 1/2" Standard Impact Wrench Competitively priced parts with equal reliability