This is American Pneumatic Tool part number 1280582362, listed as 18442 before the renumbering 18442 RETAINER 7/8 & 1 X 4-1/4, stocked at Crowder Supply as APT18442. Retaining the tool steel is its whole job. Worn retention lets the shank hammer against the bore and turns a cheap part into an expensive front head.
You will find it on the diagram for the 138 Rock Drill and 155 Rock Drill. Check it against the reference number on the diagram first; serial breaks change what fits.
If you need the parts around it, the parts diagram library has the full breakdown library, and the APT lineup covers the machines themselves. Denver stock, with same-day shipment on in-stock orders in by 4 PM ET.
- Part number: 1280582362
- Previous part number: 18442
- Manufacturer: American Pneumatic Tool
- Crowder SKU: APT18442
- Listed on breakdowns for: 138 Rock Drill, 155 Rock Drill
