Super quick leveling with stabilized line of sight Thanks to the finely tuned auto-collimation system, the Topcon line of AT-B autolevels are the ideal device for determining height differentials on busy and noisy job sites. With a completely new small lightweight design, they have excellent visibility of horizontal circle, superior gear ratio for shock and vibration and improved tangents and knobs.
Specifications
| Telescope | AT-B2 | AT-B3A | AT-B4A | 
| Magnification | 32x | 28x | 24x | 
| Field of View | 1°20’ | 1°25’ | 1°25’ | 
| Min. Focus Distance | 0.3 m | 0.3 m | 0.3 m | 
| Image | Erect | Erect | Erect | 
| Stadia Constant | 100 | 100 | 100 | 
| Focussing Speed | 2 Speed | 1 Speed | 1 Speed | 
| Accuracy (1Km Double Run) | 0.7 mm | 1.5 mm | 2.0 mm | 
| Compensator System | Magnetically Dampened | Magnetically Dampened | Magnetically Dampened | 
| Compensator Accuracy | 0.3” | 0.5” | 0.5” | 
| Compensator Range | ±15’ | ±15’ | ±15’ | 
| Horizontal Circle | 1° | 1° | 1° | 
| Water Rating | IPX6 | IPX6 | IPX6 | 
| Operating Temperature | -20°C to 50°C | -20°C to 50°C | -20°C to 50°C | 
| Width | 122 mm | 122 mm | 122 mm | 
| Length | 215 mm | 214 mm | 214 mm | 
| Height | 140 mm | 140 mm | 140 mm | 
| Weight | 1.85 kg | 1.5 kg | 1.5 kg |