This is a High Speed Digital Servo. It is designed to work with 500 Helicopters.

Features:
High Speed
Metal Gears

Specs:
Operating voltage range 4.8V-7.4V
Operating speed :
0.10sec@60°//6V
0.09sec@60°/7.4V
Torque :
6.5Kg-cm @ 6V
8.0Kg-cm @ 7.4V
Weight 40g
Working Frequency:1520us/333Hz,900us-2100us/
Ball Beaing : 2BB
15mm Coreless Motor
Size:35.5*15*32.7mm