This is the Hitec HS-5645MG Digital High-Torque 2 Ball-Bearing Metal-Geared Programmable Servo with the Universal Connector.  Because this has the universal connector, it will work with all current JR, Futaba, Hitec, and Airtronics Z radio systems and wiring.  These are a great way to outfit your next giant scale airplane, helicopter, or 1/10th to 1/8th scale car or truck.  This servo includes a blue aluminum, heat-treated servo arm.

Features: 

• EPA, Speed, Direction, and Fail-Safe Programmable
• MOSFET amplifier
• Gold plated contacts
• Three metal gears
• Dual ball bearings
• Indirect drive long life potentiometer
• High standing torque
• Watertight and dustproof
• Includes blue aluminum, heat-treated servo arm
• Works with fixed wing aircraft up to 40 pounds, helicopters, 1/10th and 1/8th on- or off-road vehicles

Includes:
One digital high torque servo with 12" wire and S/JR/Air-Z connector
One white small X-shaped servo horn.
One red Large X-shaped servo horn.
One white adjustable servo horn.
One white offset straight servo horn.
One white disc servo horn.
One blue anodized, heat treated servo arm horn.
Four 2 x 14mm mounting screws
Four brass eyelets
Four black rubber vibration isolators.

Specifications:
Speed: 0.23 sec/60° at 4.8V
Speed: 0.18 sec/60° at 6.0V
Torque: 143.03 oz-in at 4.8V
Torque: 164.2 oz-in at 6V
Length:  1.59" (40.6mm)
Width:   0.77" (19.8mm)
Height:  1.48" (37.8mm)
Weight:  2.11oz (60g)

Comments:
You must use the Hitec servo programmer (available separately) to program the fail safe and other adjustments if you choose to  The included metal servo horn will fit any Hitec servos that have a "+" stamped on top of the output shaft.