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Wearing length is the area of the jewelry that fits inside your piercing. 

Overall length (sometimes confused with wearing length) is the total measurement of the jewelry from face to face, including any additional flare or face area.

Diagram of jewelry styles with wearing length marked in green and overall length marked in red.

1. Flat face double flared plug. Wearing length is measured from the inside of the flare edges. Overall length is measured from face to face.

2. Convex face double flared plug. Wearing length is measured from the inside of the flare edges. Overal length is measured from face to face.

3. Flat face double flared plug with flat flares. Wearing length is measured from inside the flare edges (the piercing cannot rest on the flat flare areas). Overall length is measured face to face.

4. Trumpet flare style plug. The dotted line denotes where the wearing surface ends on the front, because the larger portion of the slope cannot fit inside the piercing. Wearing surface is measured from inside the rear flare edge to the area on the front flare with the same diameter measurement. Overall length is measured from face to face.

5. Sloped single flare plug. Wearing length is measured from where the slope of the flare ends to the end of the plug. Overall length is measured from face to face.

6. Top-hat style single flare with convex face. Wearing length is measured from the inside flare corner to the end of the plug. Overall length is measured from face to face.

7. Top-hat style single flare with curved rear. Wearing length is measured from the inside flare corner to the beginning of the curve (the piercing cannot rest on the slope). Overall length is measured from face to face.

8. Top-hat style single flare with groove for an o-ring. Wearing length is measured from the inside flare corner to the groove (the piercing cannot rest on the groove). Overall length is measured from face to face.

9. Labret (round or oval) with a standard concave t-back. Wearing length is measured from where the wearing shaft meets the wing to the end of the flat portion (the piercing cannot rest on the slope).

Overall length is always longer than the wearing surface because it includes other sections of the jewelry that do not rest inside the piercing. If you are ordering a piece of jewerly and you specify an overall length instead of a wearing length, your jewelry will not fit properly. Order using "overall length" at your own risk. Knowing your ideal wearing length, which can change as you stretch your piercings, ensures you're able to order jewelry that will fit well from every vendor, every time.