The most accurate ground speed sensor This top-of-the-line ground speed sensor delivers the truest velocity measurement available.·Installs easily ·Views actual ground surface for accurate speed measurement ·Can be mounted to look forward or backward from vehicle ·Velocity range 0.33-44 mph (0.53-70.8 km/h) ·Mounts at 35±5° angle and at least 24 in. (610 mm) height from target surface (mounts anywhere from 2 to 8 ft. high) ·Variety of factory output frequency settings available ·Sleek design—4 x 4 x 12.25 in. (10 x 10 x 31.1 mm) ·Weighs only 4.5 lbs. (2.05 kg) ·Achieves velocity errors of ±1-3% through in-field calibration