Product Characteristics: Adapter length: 101mm (3.98 in) Female thread: 5/8 inch Male thread: M8; Thread length: 15mm (0.59 in)Designated Use: Adapter designed for connecting reference spheres to a standard 5/8 inch male threadScope of Application: Commonly utilized as an adapter for prism polesCompatibility: Flexi reference sphere Basic reference sphere Traveler reference sphere Mini prismDelivery Contents: 1 adapter