This is a 75BBS Retract Servo used for R/C Aircraft Mechanical Retracts
with a Universal Futaba J, Hitec S, JR and Airtronics Z connector.

FEATURES
High torque
Travels 180° - full-lock to full-lock - to hold your gear in position
securely. Not proportional. Perfect for mechanical retract
installation.
Water resistant
Ball bearings

INCLUDES
Servo w/Universal connector, as well as full set of horns, grommets,
bushings and mounting screws.

SPECIFICATIONS 
Length: 44mm (1.7") Weight: 35g (1.23 oz.)
Width: 23mm (0.9") Torque: 6.6 kg-cm (92 oz-in)
Height: 25mm (1.0") Speed: 0.5 sec/60°

COMMENTS
A retract servo is a very specialized servo. It is non-proportional,
going 180 degrees, "lock to lock". They are specifically made for
mechanical retracts to lock the gear in the up and down positions.
they DO NOT have any means of end point adjustment and can not be
adjusted by ATV on a transmitter. They are only able to go 180
degrees and provide full maximum available torque at the two end
points. This is their whole purpose and intentional design, but if
someone has a unique design situation where they need other than
180 degrees available, then they must use a proportional servo,
not a retract servo. They are specifically designed to withstand
constant holding loads in the up and down positions, unique to the
use of mechanical retracts.
Pneumatic retracts do not need a retract servo. A proportional
standard or mini servo is used to move the air valve back and forth