A universal threading attachment for 4th position on an Acme Gridley 1-1/4" RB-8 screw machine has eight major assemblies:

1 - 4th Position Die Slide Assembly AM-412750
2 - Threading Lever Assembly A-392770
3 - Drive Shaft Assembly AM-413702
4 - Clutch Operating Mechanism AM-413642
5 - Die Spindle Clutch Shaft Assembly AM-413682
6 - Die Holder and Sleeve Assembly AM-412830
7 - Safety Link Assembly A-41230
8 - Loose Parts Assembly AM-41246

Below are the individual replacement parts for each assembly that make up a 4th Position Universal Threading Attachment for an Acme Gridley 1-1/4" RB-8 screw machine: