Angle measurement accuracy: 1 ", distance measurement accuracy: 1mm+1ppm(Prism) 1000m long range reflectorless distance measurement Ultra - narrow EDM laser beam, can precisely measures high voltage wire, walls, corners, manholes on the road surface, even chain - link fences and tree branches High accuracy surveying can be achieved in an easy, fast and reliable way Applied for high precision surveying areas, such as high - speed railway construction, structural monitoring and large - scale 3D measurement Windows CE 7.0 operating system, onboard software: FOIF Survey, FOIF Fieldgenius.