Metal Material: 316L Surgical Steel. The measurements are approximate! Post Gauge (thickness): 20 gauge (0.8mm), Post length: 8mm. Shell Size: 5.5mm width, 5.4mm height. Sold by Pair. Closure: threadless push pin. Metal Color: 18k gold-plated. FANSING Shell Shpaed Flat Back Earring for Helix Cartilage Conch Tragus Threadless Push Pin Labret Stud 20 Gauge 8mm 18k Gold-plated