This is the E-Flite 11.0 Gram Micro G110 Heading Lock Gyro for Micro and Mini Helicopters.  This multi-feature gyro boasts two modes (Heading Lock and Standard Rate) and compatibility with digital or standard servos, among many other features - all of this and it's lightweight too.  At just 11.0 grams, the full-featured G110 Micro Heading Lock Gyro gives micro and mini helicopter pilots all the benefits of locked-in tail control plus the ability to optimize its performance for use with digital or analog servos.  This is perfect for helicopters like the E-Flite Blade 400 and Align T-Rex.

Key Features

Specifications:

Type: Micro
Sensor Type: Piezoelectric Ceramic
Weight: .39 oz (11.0 g)
Dimensions (WxLxH): 0.6 x 1.0 x 1.0 in (16 x 25 x 25mm)
Gain Type: Single setting on-gyro or dual setting remote from transmitter
Operating Voltage: 4.2 - 8.0V
Reversing Switch: Yes
High/Low Frame Rate Select: Yes - Standard/Analog Servo and Digital Servo Support