Allows you to use smaller size filters on lenses with a larger diameter thread. The first number is the size that screws into the lens, the second number is the filter size. Step " Down" Rings May Cause Vignetting.
Reviewed by 1 customers
sorry but, I had to give this a 2 rating because, the 67mm side did not fit. It was too big, and I had to order another one. I did not send it back because the 77mm side fit, and I just may be able to use it in the future on another lens.