With this model, you always have free hands when aligning and adjusting components on metallic surfaces. The 81 SM is equipped with a ferrite magnet system that ensures good adhesion. This model has an aluminum die-cast profile with a beveled shape that makes it one of the most robust spirit levels of STABILA. The leveling and milled measuring surface are aligned precisely to each other in the production process and then permanently connected to each other to ensure maximum measuring accuracy. This means that the 81 SM has an exceptionally long service life in the construction site.This text is machine translated.