The perfect fitting thimble for quilting! This lightweight thimble stays on. The scalloped edge allows your finger to breath, and the ridged, dimpled metal cap holds the needle tip in place and pushes the needle safely without slipping. Measure your finger to the first knuckle and match to the inner diameter of the thimble, even if the size guide is a tight fit, the rubber will stretch slightly to accommodate your finger. Inner diameter: small 9/16", medium 5/8", large 21/32"