The sizing gauge works like a belt. Simply push the end through the buckle to form a ring shape. Slip the sizing gauge onto your finger. Adjust to give a comfortable fit. A good fit is when you have to wiggle the sizing gauge over the knuckle. When best fit is achieved, read off size indicated by the arrow.
The ring sizer measure sizes 3 -13 1/2 (U.S. Standard sizing). The sizing gauge measures half sizes as well. Half finger size intervals.
It is best to measure your finger when you feel your body is at a normal temperature. Do not measure your finger when you are experiencing chills or if you feel your body is warm. Take several measurements during different times of the day when you feel your body is at a normal temperature.