Solid CNC machined aluminum sphere with 25mm survey prism. Threaded 5/8"-16 top and bottom for survey tripods and tribrachs, but also includes 3/8"-16 adapters for mounting heavy photography tripods and Faro scanners. Includes 3/8"-16 studs and one aluminum cap. Does not come with tripod. Order two or more and received a pelican case for storage.