Great tool for layout with a total station. Model 003 side vial version includes a 25mm prism with sealed aluminum housing and combination socket & 5/8 x 11 thread mount. Will work with zero or -30mm offsets by reversing the direction of the prism. Includes combination plumb bob point & male thread adapter, lens cover, carrying case with belt loop, plumb bob bracket. The 40 minute side vial is fully adjustable. Weighs 10 ounces. Prism Offset: -30mm or 0