Features 1、High Accuracy: This total station surveying prism comes with a 30mm constant, which reduces errors and ensures millimeter level accuracy. 2、K9 Optical Glass: This survey mini prism features a K9 optical glass lens that is accurately ground to ensure total measurement accuracy. 3、Excellent ABS Housing: The housing of this total station prism is made of excellent ABS material to withstand weather conditions as well as daily wear and tear. 4、Wide Application: This mini prism has a wide range of applications and can be used for tunnel, subway, mine, highway inspection, etc. It is suitable for surveying instruments and is widely used in railroads, embankments, steep slopes and other industries. 5、Compact And Portable: This mini prism system is small in size and light in weight, which makes it very convenient to carry around and use. Specification Item Type: Total Station Small Prism Material: K9 Optical Glass, ABS Effective Diameter: Approx. 25.4mm/1in Constant: Approx. -30mm Package List 1 x Total Station Small Prism 1 x Lid 4 x Bathymetric Rods 1 x Storage Bag