Micro 1S LiPo driven servo.
Excellent for tiny indoor applications.
Single-Screw holds base on. Gears are replaceable.

 
Spec.
Voltage: 4.8~6.0v
Speed: 0.08~0.07sec
Torque: 0.11~0.12kg/cm
Weight: 2g (.07oz)
Spline Count: 20
Gear Material: Plastic
Gear Type: Analogue

Motor Type: Coreless
Plug: JST 1.25 Pitch

 
Operating voltage cannot be higher than 5V.
Check dimensions, this is small!