This is the HS-5055MG Sub Micro Digital Feather Servo from Hitec.
FEATURES: Programmable
Overload protection
Metal gears
Lightweight
Ideal for park flying models, indoor planes, small glider, and
micro electric helis
INCLUDES: One Hitec HS-5055MG Micro Digital Feather Servo with preinstalled
small X-shaped servo horn and screw
One 28mm straight servo arm
One 31mm servo arm
One 54mm servo arm
One 1.6x3.75mm button head screw
Two 1.7x8mm flanged button head screws
SPECS: Speed: 0.20sec/60° at 4.8V
0.17sec/60° at 6V
Output Torque: 1.3kg-cm (18.05oz-in) at 4.8V
1.6kg-cm (22.20oz-in) at 6V
Weight: 9.5g (0.33oz)
Size: 22.8 x 11.6 x 24mm (0.89 x 0.45 x 0.94in)