Remove the guess work when purchasing a ring. Made from durable plastic this ring gauge can be used time and time again. A nifty little piece of equipment which fits neatly in your pocket or bag, and covers all the options by measuring your ring size in english, usa, french or german sizes. UK and USA sizes on the front, and DE and FR sizes on the back. Comes with complete instructions on how to measure bearing in mind that when your fingers are cold they are smaller then when they are warm or hot which is when they expand, to ensure as acurate measurement as possible measure your fingers when your hands are not too cold or too hot. If the band on the ring is going to be wider then a standard 2mm, then you need to go up by half a size. Please make sure that the gague can slide on and off f.