Specification: Name Telescope Magnification 810 Eyepiece Diameter 20mm Objective Lens Diameter 42mm Prism System Roof Prism Glass Ba K4 Focus System Center Fog proof Yes Water proof Yes Nitrogen Filled Yes Phase coated Yes Size 15.5x 7.5x 18cm Net Weight 780g Package Included:1 x Telescope 1 x Storage bag 1 x Manual