These are considered Sub-miniature servos The servos are made by Hitec. On all Hitec servos the Black wire is 'ground', the Red wire (center wire) is 'power', and the yellow (third) wire is 'signal'. This servo has a Hitec/JR connector which mates directly with a 0.1" 3-pin header. This servo comes with servo arms.
These are HiTec HS-422 Servos for use in any application.
This is the chain and sprocket kit for the IG52-DB4 robot platform. It includes 10 tooth and 15 tooth sprockets, 5 feet of #25 chain, and 4 connecting links.
This is a bidirectional level shifter used to step down or up signals from 1.8V to 5V range.