Sky RC GPS Speedometer Altimeter, High Precision GPS Tester Height Speed Tester for RC Drones FPV Multirotor Quadcopter Airplane Helicopter for RC Car, Plane, Quadcopter, GSM-015

This unit works really well, if you are very careful with it. My problem is that it seems poorly put together! If I accidentally drop it from any height it explodes into a million pieces! Otherwise it is great though

Great product, accurate and reliable