The specialised tool, in addition to its traditional application for determination of vertical and horizontal lines, is equipped with solutions to make the electricians' work easier and much faster. It has practical cutouts that make it easy to precisely mark the places for mounting holes for electrical sockets, integrated electrical and logic sockets, and switches, as well as the height of their positioning. This eliminates the need to manually measure the spacing between them and the levels at which they are to be placed. The surface is printed with key dimensions and spacing, further extending the usefulness of the spirit level. The solid structure, made of a 1.6 mm thick aluminium profile, powder-coated and reinforced with transverse reinforcements, ensures durability and reliability. The spirit level is protected against damage when dropped. Resistant ends are fitted to both ends of the spirit level, which can also function as hanging hooks. 90 and 180° vials installed in the tool guarantee measurement with high accuracy of up to 0.5 mm per metre. The length of the tool is 48 cm. The tool is ideal for professional electricians and amateurs who occasionally install switches and electrical sockets.