Features: Circle neutral night lens filter for night photography for sky/star astrophotography. It can highlight the details of the starry for sky, remove stray light pollution, and restore true colors. Multi-layer coating process, water-proof, oil-proof, anti-fouling and scratch-resistant performance, protecting your camera lens. High-defination grinding optical glass lens, it can effectively reduce reflected light and greatly reduce the impact of virtual shadows on imaging, brings you clear imaging experience. 49 52 55 58 62 67 72 77 82mm are avaliable to choose, you can choose what you need. Specifications: Material: Magnesium Aluminum Alloy Diameter: Approx. 9.5 for cm/3.74 inch Frame Thickness: about 3.15 mm/0.12 inch Type: 49mm, 52mm, 55mm, 58mm, 62mm, 67mm, 72mm, 77mm, 82mm(optional) Package Includes: 1x Pollution Reduction Lens Filter note: Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.