This heavy duty aluminum professional 48 in. True Blue® I-Beam level contains our new True Blue® vials which are accurate to within 0.0005 in. per inch in all 10 level and plumb working positions. The anodized frame is super strong. The end plates are shock absorbing if the level is dropped. Top read windows are included in the level for ease in reading the vials above the level. As the dominant market leader in levels, squares and marking products, Empire Level is committed to delivering innovative solutions designed to satisfy the needs of the modern jobsite.