1、GSM-015 supports GNSS(Global Navigation Satellite System) with GPS and GLONASS system that means more satellites are orbiting the earth. 2、Support both Metric and Imperial system of Measurement: The Metric and Imperial systems can be switched easily at the user\u0027s finger. Hold and press the MODE button to change. 3、Measure Top Speed, Average Speed and Top Altitude: The user could easily view the screen while working out data such as speed, altitude, total mileage/kilometer, longitude/latitude. Stop wondering how fast your RC Car can run and how high your RC Airplane or helicopter can fly. Now all these data come at your finger with the GNSS SPEED METER by SkyRC. Features: GSM-015 supports GNSS(Global Navigation Satellite System) with GPS and GLONASS system that means more satellites are orbiting the earth. Support both Metric and Imperial system of Measurement: The Metric and Imperial systems can be switched easily at the user's finger. Hold and press the MODE button to change. Measure Top Speed, Average Speed and Top Altitude: The user could easily view the screen while working out data such as speed, altitude, total mileage/kilometer, longitude/latitude. GSM-015 also records the top speed and top altitude for instant recall after the running and helps RC fans much to fine-tune their RC gadgets to achieve better performance. Any problem, please contact our store without hesitation. Honor to serve you. Specification: Brand Name: SKYRC Item Name: Speed Meter Receiver: L1, 1575.42 MHZ Update frequency: 10 Hz Antenna type: Built-in Battery: 200mAh Li-po battery (built-in) Satellite signal reception sensitivity: -167dBm Operating temperature: 0℃ to +40℃ Storage temperature: -10℃ to +70℃ Operating humidity: 5% to 90% Size: 65.7 * 39.6 * 20.8mm Weight: 45g Note: There could be some deviation due to manual measurement. Package Information: Package Size: 18.5 * 11 * 3cm / 7.2 * 4.3 * 1.1in Package Weight: 96g Gift Box Package Package List: 1 * Speed Meter 1 * Speed Meter