Button Head Socket Cap Screw is a new kind of Socket Cap Screw, it has smaller head that can solve most problem of interfere with other components.
Thread Drive Pack V2.0 is the improvement version of Thread Drive Pack V1.0. It can be used to build thread drive system.
In this version, all parts in the demo below are included.
Note:
Makeblock Socket Cap Screw will be replaced by  Button Head Socket Cap Screw gradually, and the tool HEX Screwdriver 3mm will be replaced by HEX Screwdriver 2.5mm.