This is a light pollution cut and star enhancement filter. The diameter is 67mm. The list price is around 7000 yen. I've only used it once, but I sold the lens I used to take pictures of stars with a 67mm diameter. I like it so much that I'd consider buying a different diameter, but I no longer use this diameter, so I'm selling it. Although I like it, as mentioned earlier, I've only used it for shooting once. I couldn't find any scratches to the untrained eye. Please understand that this is a used item before purchasing. - Model Name: STARLY NIGHT PROSOFTON - Filter Diameter: 67mm - Filter Type: Light Pollution Cut Filter