This is the Tactic TSX45 High Torque Metal Gear Servo.

Features

Metal gear train with two ball bearings
First gear is plastic to reduce further damage to gear train and
motor in the event of a bind
Universal receiver connector compatible with all major brands of
radio systems
One year limited warranty through Hobby Services beginning at date of
purchase

Includes

Tactic TSX45 High Torque Metal Gear Servo
0.82" (20.8mm) diameter Round Horn
1.5" (38mm) 4-Point Horn
1.2" (31.9mm) 6-point horn
Four each, rubber Grommets, Eyelets, and 2.3 x 14mm Mounting Screws

Specifications

4.8V 6.0V
Torque: 143 oz-in (10.3 kg-cm) 151 oz-in (10.9 kg-cm)
Speed: 0.21 sec/60° 0.17 sec/60°
Dimensions: 1.6 x 0.8 x1.5" (40 x 20 x 38mm)
Weight: 1.8 oz (51 g)