Ultra fast 15 mm brushless digital servo, especially developed for tail rotor control of helicopters up to 1 metre rotor diameter.

With robust, double ball-raced metal gears The perfect match for the GY-520 gyro. Successor to the S 9257 servo with brushless motor technology.
Specification:

Mass/weight: 28.00 pond/g
Operating voltage: 4,8-6 Volts
Nominal voltage: 4.80 Volts Nominal voltage: 6.00 Volts
Torque: 22.00 Ncm Torque: 28.00 Ncm
Transit speed: 0.05 Sec/45° Transit speed: 0.04 Sec/45°
Holding power: 55.00 Ncm Holding power: 70.00 Ncm
more Specifications:
The advantages of Brushless-Motor technology:

30% faster Reaction time = better acceleration
more resistant to shock and vibration
higher efficiency, lower heat generation
no brush wear = 5 times motor life
Special-Gearbox = no backlash
Samarium-Cobalt magnets
higher resolution
same current drain as normal digital servos