Our ear tunnel self-developed structure allows the same personalized design because a small gap inside the tunnel provides enough space for the selection of charming inputs. Thanks to various possible combinations, the tunnel is particularly widely used, so it is suitable for various occasions. It has an internal thread made of 316L surgical steel, which not only has excellent quality, but also has high material durability. If necessary, scratch-resistant PVD coating provides a strong color and is further enhanced by highly polished surface. Because the very narrow edge can be screwed down on one side, the design of the tunnel gives a sense of elegance. The outer diameter of the product is listed below. Material of Products : 316L Surgical Steel / Titanium F136 Surface Treatment : Highly Polished / PVD coating Product Color : Natural Color ( Steel ) / PVD Black / PVD Gold / PVD Rosegold Outer diameter of Products : 8/10/12/14/16/18/20 The lenght:6mm All sizes are approximately All dimensions can be customized !