Decorative item, used generally to gather fabric together as it passes through, as on the front of a halter neck sundress, or as a scarf ring.

Internal measures are approximately 20mm wide x 15mm x 8mm deep

External measures are bottom: 22mm wide x  20mm hight, depth 12mm

domed top, flat back, 3 rows of 'diamanté stones' (15 in total).

Use on the shoulder of a one 'sleeved' top, or use two on bikini bottom at the sides.  

Could even be used as a decorative way to attach bag straps.