Sky-Watcher Evostar-90 (EQ3-2) 90mm (3.5"") f/900 Achromatic Refractor Telescope. They Sky Watcher EVOSTAR series are two-element air-spaced, multi-coated object achromatic refractors. They are truly outstanding, high-performance, high-resolution instruments manufactured to extremely high standards and mechanical precision. With their long focal lengths and breathtaking optical performance, they are ideal for the detailed high-power study of the moon, Planetary Surfaces and other objects in our solar system, giving crisp contrasty images. These telescope packages will stand you in great stead for a lifetime of serious astronomical viewing.