Super useful when you have multiple lenses and do not want to buy for each new filter. The build quality is impeccable and aluminum. One should only pay close attention to the numbers that you need, because there are other sets. I had mistakenly ordered a first set in which the 58 mm diameter was missing. Well from mistakes you will wisely :) Have now but this with the right adapters and am super happy. Cheap alternative to buying new filters.
