... -Short 20cm AT-B Se • Durable, Dependable, High Value Auto Levels All-Weather Dependability • Clampless, Endless Fine Horizontal AdjustmentsRapid, Stable, and ... unmatched durability and accuracy. Finely tuned magnetic damping system quickly levels and stabilizes the line of sight despite the fine vibrations ... .7kg)AT-B43.7 lbs. (1.7kg) Level Topcon Auto Levels AT-B Series