Taiwan GSO 1.25" Dielectric Zenith Mirror Taiwan GS Company is a very famous OEM manufacturer that continues to supply the highest quality parts to the world's top brand telescope manufacturer. Made in Taiwan with the finest 1.25" zenith mirror Top of the line model equipped with a high performance mirror with a 99% reflectivity. The body is made of CNC machined aluminum with a beautiful finish and excellent rigidity. The eyepiece uses brass ring tightening type. Complete with filter screws Dielectric 90 Degree Zenith Mirror Mirror: Wave Accuracy: 1/10 (6 layers dielectric multi-layer coatings, reflectivity 99%) [Sleeve diameter] 1.25 inch (31.7 mm), [Material] CNC Machined Aluminum Black Anodized [Total length] approx. 3.7 inches (95 mm) (L) x approx. 2.4 inches (62 mm) (H) x approx. 1.7 inches (42 mm) (D) Weight: Approx. 6.3 oz (185 g). Madein Taiwan The above data is the manufacturer's catalog value