This is the 8170 Digital High Voltage Heli Servo from Ace RC.
FEATURES: Compatible with 2S LiPo or LiFe batteries without needing to use a
Three titanium and one alloy aluminum gear for continuous non-stop
operation and reduced weight
High torque output with low current draw
Water and dust resistant
Aluminum middle case section for efficient heat dissipation
High performance coreless motor
INCLUDES: 8170 Digital High Voltage Heli Servo with Lead and Connector, 1.9"
(47.5mm) double sided Servo Horn
Four each, Grommets, Eyelets, 3x11mm Screws and 3mm Locknuts
SPECS: Voltage Range: 6.6-7.4V (2S LiPo or LiFe)
Pulse Width: 1520us
Torque: 14.5 kg-cm @ 7.4V
Transit Time: 0.06 sec/60° @ 7.4V
Dimensions: 1.6 x 0.81 x 1.5" (41.8 x 20.6 x 39.6mm)
Weight: 2.19oz (62g)
COMMENTS: A note on coreless motors. A conventional servo motor has a steel
core armature wrapped with with wire that spins inside the magnets.
In a coreless design, the armature uses a thin wire mesh that forms
a cup that spins around the outside of the magnet eliminating the
heavy steel core. This design is much lighter resulting in smoother
operation and faster response time.