This is for only the gear pictured 

KWA’s high torque AEG gears are hardened to withstand high pressures and provide long-lasting performance from your KM4/VM4/RM4 AEGs 2, 2.1, and 3 (WILL NOT FIT PRE-AEG 3 RM4s). Our sector gear also features a solid brass delay chip, which helps eliminate feeding issues for high speed builds.

THE SPUR GEAR IN THIS SET WILL NOT FIT THE MAGPUL PTS ERG!! THAT GEAR HAS BEEN DISCONTINUED

Please note that the spur gear in this set does NOT FIT the original Magpul PTS RM4 ERG!! The new RM4 AEG 3 is a replacement for the original RM4 ERG, and the two do not accept the same gear sets. When the model was upgraded with a higher speed motor, SLE, higher speed gears, upgraded mechanical/electrical cutoff, and rear wired battery compartment, it became the AEG 3.