This is the Sub Micro Servo included in the Two Speed Conversion Kit (TRAC4000) used on the Traxxas E-Maxx. FEATURES: Sub micro size, waterproof construction Actuates the Internal Shift Fork (TRAC3906) with the push of a button from a 3-channel transmitter YOU WILL RECEIVE: Sub Micro Servo with universal connector REQUIREMENTS: Installing at transmission and connecting to shift fork and receiver jxs 3/04/08 ir/jxs &