D203mm primary and secondary mirrors devised for Newtonian telescopes, providing superior light reflection. Spherical primary mirror and elliptical secondary mirror ensure optimal image clarity and precision for astronomy enthusiasts. Durable aluminum plating and protective film enhance mirror longevity, making this set ideal for DIY telescope projects. Easy to clean: Follow simple steps to maintain mirror surface using absorbent cotton and alcohol for clear viewing. Perfect for both beginners and experienced astronomers looking to upgrade their telescope's optical performance.