Topcon targeted accurate and simple operation with its new RL-100 Series slope lasers. A new encoding system provides remarkable grade repeatability of 5 arc seconds. All-electronic operation makes setup easy and its high-contrast display makes entering grade quick and simple. Available in single slope (RL-100S1) and dual slope (RL-100S2) models, both instruments feature up to 25 percent grade range and up to 2,500 feet of operating range.