Speed controllers for brushless motors are designed for best results with any type of motors and accumulators. - suitable for all types of accus NiCd, NiMh, Li- polymer, Li-Ion. - high frequency brake with non linear course and limited braking action - auto calibrating type with variable end point - cut off type - slow down system with safety rest of accu capacity -Modelers will enjoy extremely low (.013 ohms) resistance combined with high rate (8kHz) switching. -BEC provides power to the receiver and servos, eliminating the need for a separate receiver battery.