The Stabila 70P spirit levels have two horizontal vials, so that even long levels can be read in any position, and two vertical vials, so whatever the position of the level is, one vial is always visible. The two bridging plates allow the level to to work on uneven surfaces. Suitable forCarpenters; for wooden constructions, indoor works or wooden framework houses. Concrete workers; to set up shuttering, pre-assembled walls, girders and beams. Ironworkers; for aligning steel girders and other steel components. Measuring accuracy: 0.029° = 0.5mm/mStabila 70P-2 Double Plumb 4 Vial Spirit Level 02421. Length: 180cm (72in).