About Product:Warranty year 2: product features complete, with flagpole lock and slope ballistic correction function, and waterproof, long service life 3: 6 large packages optional, providing a full range of outdoor travel range solution 4: 450 meters range of products, From the SPI (standard version) with 5 major features; PRO (upgraded version) with 9 large features 5: upgraded version can be measured high, angle, measured horizontal distance a variety of functions optional