The Clover Knitting Needle Gauge helps you determine what size your needles are after the size wears off the needle or is just too small to see. This knitting needle gauge has holes to size US 0-19 (2.0-15.0 mm) knitting needles. This lightweight gauge is made of a thin, flexible material, so forcing a needle through a hole may deform the gauge. If you have to force a needle in, try a bigger size! This is not a hard plastic gauge. It is very thin.