hm do you mean the tools or bits that go into the tools? For tools there's 3 of them: pen which doubles as a driver, the sinkevich bolt action pen w/ bits for sinkevich knives, and now the new driver only tool.
for bits however, there are 5 I know that have been made commercially available that fit the footprint of the pen tool:
- large bit for all Shirogorov design pivot screws (Part of all pen tool sets)
- small bit for F95/111 rear screws (Part of F95 pen tool set and new driver tool)
- small bit for NeOn Lite/Ultra Lite rear screw (Part of Neon pen tool set only)
- small bit for NeOn Zero rear screw (different than above, available with new driver tool only)
- Sinkevich large bit for Shiro/Sinkevich collaboration knives (available separately for normal pen tool or available as double sided large/small bit with Shiro/Sinkevich bolt action pen)
Bits not available:
- Custom Division Inverted small screw as seen on the Hokkaido, Custom Division HatiOn, NeOn Mk2
- Custom Division lockbar insert screw, also seen on the RFT clip screw
and of course Sergey's duckfoot screws, as only he has the drivers for those
