Like most other ESCs, this one is built up using N-channel Power MOSFET`s because of their good characteristics (low DS resistance). Since this ESC has no reverse, it is not meant to be used in R/C cars or boats if reversed motor run is needed. It is more suitable for R/C airplanes. It has no BEC circuit therefore you must power the receiver and the servos from a different source.
You can either use a separate battery pack or a standalone BEC (Battery Eliminator Circuit - I / II) for this purpose. The 4N25 opto-coupler used in the device electronically isolates the ESC from the Receiver thus eliminates possible radio interferences