Right Weigh's 310-54-RK Exterior Mechanical load scale kit is designed for tandem axle drive or trailer suspensions with one height control valve. After a loaded calibration at a certified ground scale, the gauge will reliably display the on-the-ground axle group weight in pounds. When properly calibrated and used, Right Weigh on-board load scales are the most valuable tool available for maintaining safe and legal axle weights. This kit includes the gauge, mounting bracket, air line, and fittings needed to connect it to an axle group.