This is a Futaba BLS373SV S.Bus2 High-Voltage Brushless High-Torque Surface Servo.

Speed:

• 0.14 sec/60°at 6.0V
• 0.11 sec/60° at 7.4V

Torque:

• 31 kgf/cm at 6.0V
• 430.7 ozf/in at 6.0V
• 37 kgf/cm at 7.4V
• 513.9 ozf/in at 7.4V

Size: (40.5 mm x 21 mm x 40 mm) (1.59 in x 0.82 in x 1.57 in)
Weight: 84 g (2.96 oz)
Rated Voltage: DC 6.0V-7.4V
Operating Voltage: DC 4.0-8.4V