16" Degree Pitch Slope Level,Montgomery Level" /> Only level to show Degree & pitch of a slope along with the conventional level and plum measurements Rigid glass vials (UV protected) wont change shape, giving more precise readings Standard vials are accurate within + or - .000499", Arc vials are accurate within + or - .5 On top is a ruler, measuring centimeters and inches, for more convenience Box Profile, extruded from High Quality Aluminum with high tensile property/ Resistance to corrosion