The Bee Line 22000 Rear Axle Aligner allows users to accurately position the rear axles perpendicular to the vehicle’s centerline so the wheels travel in a straight line. The user-friendly construction allows novices to set up the Rear Axle Aligner, and one person can take all necessary measurements in a few minutes, the company said. The unit calibrates reliably and quickly to assure consistent accuracy with no added expense or service fee. The wheel cradles weigh less than 20 lb., and the rear beam weighs 10 lb. A long life ni-cad battery powers the laser for up to 20 hours before recharging. This unit does not require access to AC power.