This level is perfect for professional carpenters, framers, plumbers, concrete workers, and hobbyists who demand accuracy and precision. 2 Vials Hold/lock measurement feature Easy to read large display with backlight, Display automatically rotates for ease of use Precise measurements in degrees, percent or feet and inches Audio indicator 2x 3V button batteries included Specifications Measuring Range: 0–360° (4 x 90°) Accuracy Electronic module 0°/45°/90°/135°/180° °, ±0.1° -1° to 89°, ±0.2° Spirit level In normal position: 0.5mm/m In reverse position: 1.0mm/m