The AHRS-G mini SW is a battery powered attitude and heading reference system that provides pitch and bank information as well as magnetic heading, inclination, gravity load and yaw rate wirelessly to your portable device. Unlike the gyros inside your iPad or other similar systems, the AHRS-G mini is the only AHRS system that guarantees a Zero drift per hour rating. Meaning there is no calibration required at any point. Just set it on a level surface and you can count on an accurate horizon for the rest of the flight. This model provides AHRS data only - no air data.