Accurately measures plumb, level, 45?? and slope. its solid aluminum frame is highly durable to survive even the toughest jobsite abuse. it was also designed to be easy and convenient to use and its top-read window lets you view the level vial easily from any angle and the surroundviewr vials are larger than the competition's at 1/2 in. diameter and reflect ambient light, making them exceptionally easy to read. this level also features powerful griptightt magnets that hold to flat or round ferrous metal surfaces for convenient, hands-free use while the v-groove frame fits easily on pipe and conduit.