Most popular Ammco Style Economy Negative rake cutting bits for Disc/Drum Lathes. Replaces all Ammco 906914 bits. Use On Ammco Models 1000, 1001, 3000, 4000, 4100, 7000, 7700. For On-The-Car models 700, 705 & 710. Drum Side of Machine on Model 3850 Brake Lathes. FMC, John Bean, Barrett, Snap-On-the-Car Lathes. For Models 500 Series On-the Car RTI Style Lathes using negative rake. 6 cutting edges. Hofmann/RJ West Negative rake bits for Disc/Drum Lathes. For Model 660 Lathes. RELS Negative Rake Rotor Bits. For Model 2000 Disc/Drum Lathes. 6 Cutting Edges for use on OEM# 90614-10 for Ammco. OEM# 90817 for FMC, John Bean, Barrett, Snap-On-the-Car Lathes. OEM# 221-580-2, 221-617-2 for Hofmann. OEM# 45001 for RELS.