GWS Mini Park Series Servo. (smaller than a standard size servo, though larger than Nano/Pico Servos) Model: PARK HPX Size: 30.86x16.17x28.5 Weight: 19g Speed: (4.8v: 0.07sec)(6v: 0.05sec) Torque: (4.8v: 3kg)(6v: 3.6kg) Excellent servo for Heli Tail Rotors for High Speed Gyros
Just a side note: It does not work all that well with the HK401b as the pulse width is wrong. I recommend Turnigy gyros instead