KTS-442R10LCN can measure 5km with a single prism and 1000m without prism. It has been improved in the circuit structure and mechanical structure. The whole circuit works more stably and reliably, forms effective protection of current and prolongs the working time of battery. The Prism-free infrared laser total station has the function of laser centering and laser pointing, which makes it more visual and intuitive. SD memory card expands the mass storage by 1G.