Thickness and gauge:
The word gauge refers to the thickness of the jewelry.
The gauge size works in reverse, the higher the number the smaller the gauge (thickness) .
For example : 20 gauge will be thinner than the 8 gauge.
If you need to know the gauge of your jewelry the best way would be to go back and check with your piercer or stick with the standard sizing for piercings. Most Piercers have a standard size of their own that they prefer to use for starter jewelry. Please Note: It’s important to ask your piercer the gauge of needle they’re using.
Diameter:
The diameter is a measurement that has been used for circles or other round shapes.
In a piercing the diameter is used to measure the size of the ring, the overall diameter is the internal size of the ring.
The internal diameter is important when you buy Captive Bead Rings, Horseshoe Circular Rings and Hoops. Especially since the ring goes around the body part like a lip ring, nipple ring, nose ring etc. The easiest way to find your internal diameter size is to measure from your piercing hole to the edge of you lip , nose, ear or to the place you want your jewelry to drop down to.
Length:
The length measurement is referring to the length of the jewelry bar NOT the length of jewelry itself.
The length of a belly ring (curved barbell) is measured as the distance between the bottom and the top ball same as with a tongue ring(straight barbell) .
Always Remember, it’s very important to know the right length of your body jewelry !
If it’s too short, it can pinch your skin and cause your body to reject the jewelry, making it uncomfortable to wear and keep on.
Ball Size:
Balls are also measured by the diameter from side to side.
Common ball sizes are 3mm, 4mm,5mm ,6mm
3mm and/or 4mm are usually used on curved barbells
5mm and/or 6mm are used for the top of a belly ring or on a tongue ring .
Please Note: Almost every ball can fit on any shaft if they are the same gauge and same thread size.