Features GREAT REFLECTION: This survey prism is designed for excellent reflection, largely improving the measurement imaging and accuracy. OPTICAL GLASS: This prism uses optical glass, which enhances reflection ability, with full texture, clear and bright, making the measurement more accurate. EASY INSTALLATION: Comes with a compact size and a light weight as well, the prism reflector is very convenient to install within minutes. LONG LASTING: The total station prism is made of ABS material, which is sturdy and firm, not easily be damaged, ensuring long lasting use. WIDE APPLICATION: Total station prism can be installed in tunnels, roads, bridges, dams, buildings or some other fixed places or objects to measure distortion and displacement. Specification:Item Type: Mini Peanut Prism Replacement Model: AY03 Material: Optical Glass, ABS Glass Surface Diameter: Approx. 35mm / 1.5in Application: Tunnel, subway, mine, highway and other detection Package List:1 x Mini Peanut Prism Replacement 1 x Cover Package List 1 x Mini Peanut Prism Replacement 1 x Cover