The Prism Pole Topo Shoe helps you secure exact height measurements on soft surfaces. This survey rod extension evenly distributes the weight of your survey rod or prism pole so it doesn’t sink into the ground and throw off your calculations. This prism pole accessory is invaluable in areas where extremely precise height measurements are important, such as topographical surveys. The high-quality aluminum body is corrosion resistant. It is 3.37” in length and weighs 0.34 lb (0.15 kg). The Prism Pole Topo Shoe fits most poles.