9g Digital Hybrid Metal Gear Reverse Servo with 500mm (20") Lead from Freewing - MD31093R-500
This servo is used on various Freewing jets such as the J-10A. It can be used with other aircraft with compatible specifications (see below).
Features:

Lightweight, efficient high torque metal gear servo perfect for mid-sized to large EDF jets

Includes:

Freewing 9g Digital Hybrid Metal Gear Reverse Servo with 500mm (20") Lead
4 mounting screws
3 servo horns