AT-BK Series
Durable, Dependable, High Value Auto Levels
- 3 Models – 32x, 28x, and 24x Magnifications
- Rapid, Accurate, and Stable Automatic Compensation
- Ultra-Short 20cm (7.9 in.) Focusing
- All-Weather Dependability
- ±5 Degrees Self-Leveling Range
- Clampless, Endless Fine Horizontal Adjustments

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Rapid, Stable, Durable Compensator
The compensator AT-BK Series incorporates four suspension wires made of super-high- tensile metal that features minimal thermal expansion coefficient, providing unmatched durability and accuracy. Finely tuned magnetic damping system quickly levels and stabilizes the line of sight despite the fine vibrations present when working near heavy equipment or busy roadways.
20cm (7.9 in.) – Short Minimum Focus
The AT-BK Series can focus on objects at 20cm (7.9 in.) in front of the telescope. This feature dramatically facilitates working in confined spaces.
Horizontal Circle for Measurement
Horizontal angles can be directly read in 1° or 1gon units. Free rotation feature allows you to read any angle from zero. The circle is covered for protection against dirt and scratch. The readout window is located below the eyepiece for quick reading.
All-Weather Dependability
With the IPX6 rating, the instrument is protected against powerful water jets from all directions, meaning the AT-BK Series withstands a sudden shower or torrential rainfall. The advanced protection design also deters clouding or condensation inside the telescope.
| Specifications | |||
| Telescope | AT-B2K | AT-B3K | AT-B4K |
|---|---|---|---|
| Magnification | 32x | 28x | 24x |
| Field of View | 1°20’ | 1°25’ | 1°25’ |
| Min. Focus from center of the instrument | 0.3m (1 ft.) | ||
| Image | Erect | ||
| Stadia | Yes (1:100) | ||
| Focusing Knob | 2-speed | 1-speed | 1-speed |
| Accuracy (1km double run leveling) | |||
| Without Micrometer | 0.7mm | 1.5mm | 2.0mm |
| (0.03 in.) | (0.06 in.) | (0.08 in.) | |
| With Micrometer | 0.5mm | n/a | n/a |
| (0.02 in.) | |||
| Compensator | |||
| Type | Pendulum compensator with magnetic damping system | ||
| Setting Accuracy | 0.3” | 0.5” | 0.5” |
| Working Range | ±15’ | ±15’ | ±15’ |
| Horizontal Circle | |||
| Minimum Division | 1°/1gon | 1°/1gon | 1°/1gon |
| General | |||
| Water Resistance | IPX6 (IEC 60529:2001) | ||
| Operating Temperature | -4°F to +122°F (-20°C to +50°C) | ||
| Width | 5.12 in. (130mm) | 5.12 in. (130mm) | 5.12 in. (130mm) |
| Length | 8.46 in. (215mm) | 8.46 in. (215mm) | 8.46 in. (215mm) |
| Height | 5.51 in. (140mm) | 5.51 in. (140mm) | 5.31 in. (135mm) |
| Weight | 4.1 lbs. (1.85kg) | 3.7 lbs (1.7kg) | 3.7 lbs (1.7kg) |
Brochure
Download AT-BK Series Brochure
