This is the Savox SC0252MG Standard Digital Servo.

Features:

• Precision metal gears forms a strong and solid framework
• Strict production and quality control of plastic components
• Totally Green – from materials to production, these servos are environmentally friendly.
• Ideal for 30 size airplane or surface vehicle steering applications.

*NOTE: Certain combinations of receiver and ESC have been found to cause "Brown Out" issues when combined with Savox servos. An , or may be needed for efficient, glitch free operation in low voltage electric applications.

Specifications: 

• Speed @ 6.0V: 0.19 sec/60°
• Torque @ 6.0V: 145 oz-in / 10.5 kg-cm
• Weight: 49g 
• Bearing: Dual
• Type: Standard
• Gear: Metal
• Case: Plastic
• Output Shaft: 25T Spline (Futaba)
• Case Size (LxWxH): 40.7x20x39.4