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
            regulator
          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
          Instruction Sheet

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.

                                                                   jxs 01/15/13
                                                                         ir/jxs