This is the Hitec MD89MW-CAN servo used for the three-bearing swivel module (3BSM). Unless you need a replacement servo individually, it's reccomended to purchase the Electronics Pack to receive a combo discount.

Spec Highlights
Serial Protocol: CAN Bus (2.0A or 2.0B)
Stall Torque: Up To 118.04z•in (8.5kgf•cm)
Max Speed: 0.11s/60°
Operating Voltage: 4.8 ~ 7.4V
Weight: 25g
Controller: High Resolution 32-bit Programmable Digital Circuit
Position Sensor: Magnetic Encoder
Motor Type: Coreless Metal Brush

Programmable Functions
End Point Adjustments
Direction
Fail Safe
Dead Band
Speed (Slower)
Soft Start Rate
Overload Protection
Data Save / Load
Program Reset