This is Chicago Pneumatic part number 4700W65101 O-Ring, stocked at Crowder Supply as CP-4700W65101. It seals a pressure joint inside the tool, and because elastomer takes a set long before the metal around it wears, it is one of the first items to replace when a machine starts weeping air or oil.

The full diagram library is where to start if you are working back from a machine or send the model and serial and we will confirm it. Complete tools sit on the Chicago Pneumatic lineup. Denver stock, with same-day shipment on in-stock orders in by 4 PM ET.

• Part number: 4700W65101
• Manufacturer: Chicago Pneumatic
• Crowder SKU: CP-4700W65101