Our corner cube prism for land surveying instrument retroreflectors has not only been well sold in China, but also has been exported to Europe, USA, and Japan. Our overseas clients include Leica, and Sokkia. We guarantee high quality products at a cheap Chinese price. Corner cube prism has three mutually perpendicular surfaces and a hypotenuse face. Light entering through the hypotenuse is reflected by each of the three surfaces in turn and will emerge through the hypotenuse face parallel to the entering beam. The prism thus returns the entering beam to its source. The advantage of the corner cube prism over mirror is that the incident angle of incoming beam can be very large. Specifications: 1) Material: BK7 2) Φ: 64, 50.8, 38, 25.4, 12.7mm 3) H: 48, 32, 26, 19, 10mm 4) α: ±5 5) S/D:: 60/40 6) Facial contour: λ/10