Flesh plug

A plug (sometimes earplug or earspool), in the context of body modification, is a short, cylindrical piece of jewellery commonly worn in larger-gauge body piercings. Modern western plugs are also called flesh tunnels. Because of their size — which is often substantially thicker than a standard metal earring — plugs can be made out of almost any material. Acrylic glass, metal, wood, bone, stone, horn, glass, silicone or porcelain are all potential plug materials.

Plugs are commonly, and have historically, been worn in the ears. They can, however, be inserted into any piercing.

In order for a plug to stay put within a piercing, the ends of its cylindrical shape are often "flared out," or the plug is fastened in place by o-rings. Combinations of these two methods may also be used.

A flesh tunnel is a hollow, tube-shaped variety of body piercing jewellery. It is also sometimes referred to as a spool, fleshy, earlet, expander, or eyelet.

A flesh tunnel is usually used in stretched or scalpelled piercings. Flesh tunnels are made in smaller gauges. However, the smaller the gauge the smaller the effect to see through the plug becomes. A person may choose to wear flesh tunnels instead of flesh plugs because they weigh less; at higher gauges, the weight difference increases. Flesh tunnels may be worn with a captive bead ring or other object passed through them.

Flesh tunnels are fashioned from a broad range of materials, including surgical steel, titanium, Pyrex glass, silicone, acrylic glass, bone, horn, amber, bamboo, stone, and wood. Flesh tunnels, like flesh plugs, may feature a decorative inlay or semi-precious stones. Some flesh tunnels have flares to keep the jewellery from falling out. If there are no flares, grooves may be cut near the edges to allow rubber or silicone o-rings to hold the jewellery in place. The back of the flesh tunnel may also screw off. A flesh tunnel may also have an internally threaded backing, as externally threaded pieces can rip freshly stretched ears.

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Wikipedia