Using these KnitPro Mindful Collection interchangeable lace needle tips is easy. First, choose the cable that suits your project. Whether you like a swivel or non - swivel cable, just connect the 4'' US 7 tip to it. When making a 16 or 20 needle, make sure to use the 4 tips for a functional setup. As for maintenance, after each use, simply wipe the needle tips with a clean, dry cloth to keep them in good condition. Remember, although all tips fit all cable sizes, using the right combination as mentioned is important for the best knitting experience.