This is a PVD Black 316L Grade Steel ball closure ring (BCR) which is available in several sizes as follows:
1.2mm wire is available in 6mm, 8mm and 10mm and has a 4mm ball.
1.6mm wire is available in 10mm with a 4mm ball and in 12mm with a 5mm ball.
The ball has dimples either side of the ball which is held in place by the tension of the ring.
Suitable for an initial piercing.
