This is a RCBS , model 09550.
The RCBS(R) Universal Primer Arm-2 is designed for fast" accurate primer seating. Primer plugs and sleeves are included for large and small rifle and pistol primers. Changing sizes is fast and easy" taking less than 60 seconds. The arm fits Rock Chucker(R) II" JR" Reloader Special and most C presses. Note: Not for use with Rock Chucker(R) Supreme.
Features:
Changing sizes is fast and easy
Primer plugs and sleeves are included for large and small rifle and pistol primers