With a 90mm large aperture and 800mm focal length, SVBONY SV520 telescope collects more light, allowing for better observation of deep-sky objects. Compared to other entry-level products with a 70mm aperture, it provides brighter and clearer images. This powerful telescope is an ideal choice for astronomy beginners, featuring well-matched components and easy assembly. We've also created an installation video and offer dedicated technical support to help you get started with ease. The altitude-azimuth mount features a worm gear drive system, ensuring smooth and precise movement. With 360° horizontal and 90° vertical adjustment, it maximizes your ability to meet all observational needs. The package includes a K25mm eyepiece and a moon filter. You can also pair it with high-magnification eyepieces and other filters to meet a variety of observational needs. SVBONY polarizer lens filters lens polarizing filter acts like a dimmer switch for the telescope; reduces brightness of the Moon or planets; glare or reflections; improves the objects contrast for great clear viewing. Adjust the amount of light transmission from 1% to 40% by rotating the filter housing. Reduces brightness of the Moon or planets for great clear viewing. Finer control of the image brightness compared to a standard fixed-transmission telescope filter for optimal performance.