This is the Low Profile Retract Servo by Hobbico.
This Servo is Non-Proportional (Travels 180° Without Stopping).
FEATURES: Cored Motor Design.
Universal Connector Fits Futaba, Hitec, JR, KO Propo, Airtronics Z,
and Tower Hobbies. KO Propo.(Does not fit old Airtronics "A" plug.)
Travels 180° - full-lock to full-lock -- to hold your gear in
position securely. Not proportional. Perfect for mechanical retract
INCLUDES: One Low Profile Retract Servo
One Servo Accessory Bag (horns, grommets, screws, bushings)
SPECS: Torque @ 4.8V: 92 oz-in (6.69 kg-cm)
Torque @ 6V: 114 oz-in (8.29 kg-cm)
Weight: 1.23oz 35g
Speed: .5 sec @ 60°
COMMENTS: A retract servo is a very specialized servo. It is non-proportional,
going 180°, "lock to lock". They are made specifically for
mechanical retracts to lock the gear in the up and down positions,
and DO NOT have any means of end point adjustment and cannot be
adjusted by ATV on a transmitter. They are only able to go 180°
and provide full maximum available torque at the two end points.
This is their whole purpose and intentional design. If someone has
a unique design situation where they need other than 180° available
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