I have been researching for several months the interchangeable circular knitting needles. I just bought a set somewhat like the one shown here. I believe having a set like this is good because if you are like me you never have the correct needle or lengths to do your knitting project. I find myself going a size or 2 different from what the project states because I didn’t have size needed. With an interchangeable set you have around 9 pairs of needles and about 3 different length sizes. This set has strong reviews for the product. Check it out and see how you like them.