Large cross section for 5 times stronger level. Block vials for durability and accuracy to 0.0005". Magnified center vial maximizes vial readability. Robust metal and over-mold end caps provide shock resistance. Die-cast center vial holder maintains level accuracy under abusive work conditions. Bridged center vial for continuous marking edge and body rigidity. Primary users: General contractors, roofers, framers, HVAC and technicians.