This is the Futaba S9650 Digital High Torque, High Speed Mini Servo.
One servo w/ 4 rubber grommets and brass eyelets, and one .83" (21mm) diameter round horn
Length: 43mm between centers of side mounting holes
35.5mm servo body length
42.5mm between the centers of standard mounting holes
Weight: .9oz (26g)
SPEED: .14 sec/60° @ 4.8V
.11 sec/60° @ 6V
TORQUE: 3.6 kg-cm @ 4.8V (50 oz-in @ 4.8V)
4.5 kg-cm @ 6V (62.5 oz-in @ 6.0V)
Will NOT work with these Futaba radios (4FG, 5FG/K, 6FG, 6FG/K, 7FG/K New Terratop, 3EGX, 3PGE, 2NL, 2LGX, 2FR, 2PK series)
These radios have a servo neutral signal of 1310us not compatible with this servo.
***For MAXIMUM performance, a 6.0V battery is recommended***