This is a High Torque, High Speed Digital Mini Servo from Futaba.

FEATURES: Coreless motor: conventional servo motors have a steel core armature
wrapped with wire that spins inside magnets. In a coreless design
the armature uses a wire mesh that forms a cup that spins around
the outside of a magnet. This arrangement is much lighter, which
results in smoother operation and faster response time.
Nylon Gears
Can be used with 1/12 or 1/18 scale vehicles and electric helicopters
One year warranty

INCLUDES: One servo w/ 4 rubber grommets and brass eyelets, and one .83" (21mm)
diameter round horn
Instruction/Precaution sheet
Warranty Card

SPECS:    Dimensions: 1.4 x 0.6 x 1.1" (36 x 15 x 29mm)
Weight: .92oz (26g)
SPEED: 0.14 sec/60° @ 4.8V
0.11 sec/60° @ 6.0V
TORQUE: 50 oz-in (3.6 kg/cm) @ 4.8V
63 oz-in (4.5 kg/cm) @ 6.0V

COMMENTS: 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***