Gold PVD labret stud in 1.2mm surgical steel set with a black onyx stone. This is an internally threaded labret.  The bar is available in 6mm or 8mm lengths and the onyx stone is 2mm in diameter. The base is 4mm diameter.

Flat backs (Labrets) are suitable for a variety of piercings. Lips, Tragus, Helix, Lobe etc Internally threaded labrets are better than externally threaded as there is no thread to catch on the piercing as you insert it. 

1.2mm x 6mm
1.2mm x 8mm