This gear kit contains 60 kinds of 0.5 modulus gear, the gear shaft 102A which there is copper gear, also the 2.3MM and 3.17MM gear included, some rack, worm and belt may you need too. Gears are made of ABS plastic and meets DIY requirements.
Pololu 4-Channel RC Servo Multiplexer (Partial Kit)
Super Micro 0.08sec/60degree 0.7kg.cm Analog Servo FS0403.
Tower Pro 9g SG-90 Mini Servo