Metal Material: 316L Surgical Steel. The measurements are approximate! Post Gauge (thickness): 16 gauge (1.2mm), Post length: 6mm. Trio CZ Stone Size: 6.4mm width, 6.4mm height. Sold by Pair. Closure: internally threaded. Metal Color: highly polished. FANSING Cartilage Earring Tragus Stud Trio CZ Stone Flat Back Earring for Helix Conch Internally Threaded Labret Stud Emerald 16 Gauge 6mm