Needle Gauge: If the size mark of the needle is worn out, it can help you quickly confirm the size. Use notches to determine the size of crochet hook WPI Specification: Quickly determine the WPI rating by counting the number of yarn wraps per inch or laying the yarn along the black strip until you find a match Premium Materials: Made of strong and durable high quality wood, knitting needle sizer tool will not warp or bend with the use, smooth appearance so your yarn won't snag or up Convenience: Convex notches are used to fix on the spinner to avoid yarn unraveling. Round hole can be paired with gift chain and lobster clasp, easy to carry or hang anywhere you want Multifunctional: Made of high quality wood, clearly marked and multi-functional, you can quickly determine the needle number, WPI and yarn weight. A perfect multifunctional sewing and knitting tool for everyday life