WWAKE threadless flat back studs are super comfortable and make it easy to wear all day everyday. 14k solid recycled yellow gold Flat Backing: 14k yellow gold, 1.0mm diameter (18ga) Flat Backing Length: available in either 5mm or 7mm length These backings are exclusively for WWAKE flat-back earrings, and won't work for other WWAKE earrings | Flat Back - Single Earrings Size 0mm in 14K Yellow Gold | WWAKE