I bought this at an electronics store today. I was going to attach it to my single-lens reflex camera lens, but... The ring diameter wasn't wide enough, so it's difficult to use, and I'm listing it early. Please, someone use it! I want to sell it quickly, so I'll lower the price a little!! I only opened the 77mm ring part, but I haven't powered on the main unit, so it's unused. All ring parts included: 49, 52, 55, 58, 62, 67, 72, 77 (mm)