The SitePro Traverse Prism System is for precise setups and traversing applications. Ithas 2.5X optical plummet (built-in on 05-3511 tribrach adapter)60-second plate vial, adjustable Precision-machined axis rotates 360. Compatible with all prisms with a 24.9 mm bayonet base. It has an Adjustable height:100 mm-to-120 mm. Traverse tribrach adapter fits all standard three-prong tribrachs. The over point accuracy is 0.5 mm at 1.5 m.