The Double Tube Bracelet is a fabulous piece of Jewelry to add to your collection. It will go with all of your other Body Piercing accessories. The thickness of the bracelet is approximately 1/4 inch. wide and it is available in three different sizes. We measure these bracelets just as we do our Captive Bead Rings, which is the inside diameter. To measure for this just lay a ruler across your wrist to determine the size bracelet that you will need. Also to check your measurement you can use a cloth tape measure or a string to measure your neck and then divide that measurement by 3.14 and that will give you the diameter if your neck where a perfect circle. Because the shape of your neck is not an absolute perfect circle this is just used as a way to check your measurements.