Powder-coated frame with milled measuring surface and 2 securely bonded vials. Acoustic guidance. Display may be read in inverted position. May be used to measure angles and can be calibrated by user. Specifications: Measuring range: 0-90°. Accuracy of vials: 0.5mm/m (normal position) 0.75mm (overhead measurement). Accuracy of electronic inclination measuring: 0-90° = 0.05°, 1-89° = 0.2°. Protection class IP54. Measuring units: °, %, mm/m, inch/ft.