Covers Almost All Your Bases
They seem well made and are easy to use. It's possible to avoid the "cone effect" if you need to use 3 or more rings by reversing every second one (attach it from the inside instead of the outside). I bought these to adapt a Raynox macro lens filter to various size lenses and so far so good! The only thing missing are rings for the 43 mm to 49 mm and 49 to 52 mm steps ... if you have a Canon 50 mm 1.8 STM lens with a 49 mm filter ring, you would not do well with this product.