This ring sizer works like a zip tie, simply push the end through the loop to form a ring. Slip the looped ring sizer onto your finger, and adjust the tightness to find your perfect fit. It should be snug, but not too tight. You should be able to slip the sizer easily over your knuckle. Once you find a comfortable fit, note the size indicated by the arrow. If you are a half size, we recommend sizing up to the next full size as we do not carry half sizes.