14K gold-filled endless hoop.
Hoop size is 14mm in diameter. 
Important to note that these endless hoops are gold filled and not gold-plated and made with actual 14K gold. 
The shells all differ in sizes (roughly 2-5mm differences), not one is the same. These are gold plated.
 
These earrings are perfect for long-wearing as the hoops are gold filled - also comfortable as the shells are subtle and the endless hoop design means they stay in the ear extremely well. (Great if you're an adventure go-er - they never come out!).