This is the Hitec HS-646WP High Voltage Analog Waterproof Ultra Torque Servo.
$44.99
Hitec HS-646WP Servo with 1.02" (26mm)
Single Arm, 2.3" (59mm)
Double Arm, 1.6" (42mm)
Four Point Horn, 0.98" (25mm)
Single Arm
Mounting Hardware
Waterproof-industry first IP67 rating, ranking these as among the
most durable and reliable servos for wet conditions
3-pole motor
Dual ball bearings