This is the Hitec HS-646WP High Voltage Analog Waterproof Ultra Torque Servo.
A popular servo for smaller airplanes, heli’s, boats, cars and trucks, the HS-81 offers a fine balance between speed and torque.
Dual ball bearings. Digital and MOSFET amp programmable (see COMMENTS). Indirect drive potentiometer for long life. Narrow dead band width and high standing torque.
This is the Hitec HS-65HB Mighty Feather Micro Servo with Universal Futaba J, Hitec S, JR and Airtronics Z Connector.
The HS-55 sets the standard for affordable performance, offering precision components that have been engineered to provide long lasting trouble free service. The HS-55 is a great choice when it comes to controlling smaller electrics and Park Flyers.