This 40A speed controller is a good affordable solution to power your brushless motor.

 

Specification

40A:
Size: Approx.68 x 25 x 8 mm
Weight: Approx.39g
Working current: 40A
Maximum current: 55A (10 seconds)
BEC: Yes, 2A / 5V
Applicable battery type: 2 - 3 Li-Po, or 5 - 9 Ni-MH / Ni-Cd
Maximum speed: 2 pole motor 210000 rev / min, 6 pole motor 70000 rev / min, 12 pole motor 35000 rev / min

Features

Safety arming feature: Regardless the throttle stick position, the motor will not spin after battery connected. 
Throttle calibration funtion: Throttle range can be calibrated to be compatible with different transmitters.
User programmable - Multiple program methods supported such as transmitter stick, LED Program Card.
Compatible with Lipo and NiMH battery.
Timing can be changed to be suitable for different brushless motors.
Full protection: Low voltage cutoff protection / Over-heat protection / Throttle signal loss protection.

Programmable Features

Brake- Off/On
Battery Type- Lipo or Nimh
Cuttoff Mode- Soft/Off
Cuttoff Threashold- Low/Medium/High
Start Mode- Normal/Soft/Super Soft
Timing- Low/Medium/High