Complaint
| Model | AT-B4 | AT-B3 | AT-B2 | |
| Telescope | Objective aperture | 32mm(1.26 in) | 36mm(1.42 in) | 42mm(1.65 in) |
| Magnification | 24 × | 28 × | 32 × | |
| Image | Erect | |||
| Field of view | 1°25' | 1°20' | ||
| Resolving power | 4 .0" | 3 .5" | 3.0" | |
| Shortest focus | 0.3m (1.0 ft)(from center of instrument) | |||
| Stadia multiplication constant | 100 | |||
| Stadia additive constant | 0 | |||
| Coarse sighting | without | with | with | |
| Compensator | Damping system | magnetic | ||
| Working range | ±15' | |||
| Setting accurancy | 0.5 " | 0.3" | ||
| Leveling accurancy | 2.0mm | 1.5mm | 1.0mm | |
| Horizontal circle | Diameter | 103mm(4.1in) | ||
| Graduation/estimation | 1°(1 gon)/ 0.1°((0.1 gon) | |||
| Sensitivity of circular level | 10'/2mm | |||
| Horizontal fine motion screw | Double-sided endless drive | |||
| General | Water resistance | IP66 | ||
| Base | Concave and flat | |||
| Base screw | ¢5/8in | |||
| Size(W*D*H) | 215*130*135mm | 215*130*140mm | ||
| Weight | 1.70kg | 1.85kg | ||
| Case | 1.38kg | |||
