Unique tool to plumb pipes, posts, levelling RSJ’s & other applications where vertical or horizontal is required. Hinged Patent body opens to any angle & allows use on square, round & hexagonal posts, as well as girders. Elastic straps for non magnetic surfaces & magnets for steel fence posts. Plastic construction with acrylic vials. Size 188 x 133mm. Accuracy 1.75mm per 1M = 0.1°.