Step up your competition! Viper’s Throw Line Marker helps keep players in line and toes behind the line. A precisely engineered Axis Rectifier Scale helps you adjust your stance consistently throw after throw, running your average even higher. High quality printing and heavy duty resin will stand the test of time, after countless games. The sleek design and elegant sharpness complement a modern décor much better than that old piece of masking tape. Installation is a breeze, just measure, center, peel and stick.