Sola Plastic Cast Torpedo Scaffolder's Level - PT 25 Rugged ABS Plastic Housing 2 Easy Read Vials Accuracy  1mm/M Shockproof acrylic block-vials. Sonic welded not glued. Vials will neither crack nor break when used at the jobsite Lifetime guarantee against leakage and fading of vial: In proper use of the level, vials will neither leak nor fade in the sun