Ordering by number: this is 9232050110, the Atlas Copco lock ring. This is location hardware it keeps parts indexed to each other under impact loading, and it is normally replaced any time the joint is opened.
The published breakdown lists it on the Cobra Combi Gas Breaker/Drilll- before 2010 and Cobra Combi Gas Drill/Breaker, and on 1 other machine. Compare it to the reference callout on the diagram to be sure it is the position you need.
Everything else on that machine is one page away on the full diagram library; complete tools are on the Atlas Copco tool range. It ships out of Denver, same day on in-stock orders placed before 4 PM ET.
- Part number: 9232050110
- Manufacturer: Atlas Copco
- Crowder SKU: AC-9232050110
- Listed on breakdowns for: Cobra Combi Gas Breaker/Drilll- before 2010, Cobra Combi Gas Drill/Breaker, Red Hawk Gas Breaker/Drill

