The heart of Stabila level is the patented epoxy locked vial system. Guaranteed accurate for life... no screws, no springs, no nuts, no bolts, no rivets -- never needs adjusting! Ready for use off the shelf or out of the package. Professional work requires professional tools. Stabila spirit levels are unparalleled with regard to their accuracy and dependability. The secret - the vials made of block acrylic glass are firmly epoxy-locked in the frame. A perfect system. The vial is firmly cast in the aluminum frame profile with non-shrink resin.

No re-adjustment, no realignment, no tensioning against springs made of steel or fatigued plastic, no welding or clamping stresses. Just as accurate after 20 years as on the first day.