1、360 DEGREE PRISM: Designed with 6 separate prisms connected together, allows the measurement beam to be reflected from any angle. 2、REFLECTIVE EFFECT: Copper or silver plated film enhances the prism reflective ability, clear and bright, improving measurement accuracy. 3、SPECIFICATIONS: The prism has a constant of +23.1mm and an effective diameter of 25.4mm, which has a wide range of applications. 4、EXCELLENT GLASS: This universal prism lens is made of excellent K9 glass, which has high transmittance, making measurement easier. 5、WIDE APPLICATION: Widely used in tunnels, railways, dams, mines, highways, steep slopes, and other detection, simple and practical. Item Type: 360 Degree Prism Material: K9 Glass, ABS Constant: +23.1mm Effective Diameter: Approx. 25.4mm / 1in Use: Widely used in subway, railway, tunnel, dam, steep slope, mine, highway and other detection 1 x Universal Prism 1 x Storage Bag