Super quick levelling with a stabilised line of sight Thanks to the finely tuned autocollimation system, the AT-B series of auto levels is ideal for determining height differentials on busy and noisy job sites. With a small and lightweight design, they have excellent horizontal circle visibility, superior gear ratios for shock and vibration, and improved tangents and knobs.Work in all conditions The AT-B series levels feature world-class auto-compensation, incorporating four low thermal expansion suspension wires. This gives you a stabilized line of sight for perfect measurements when working on busy sites or near heavy machinery.An IPX6 rating ensures that the AT-B is tested to withstand sudden showers or torrential rainfall. The advanced protection design also prevents clouding or condensation inside the telescope.