I designed this opening ring to hang charms on, it has a 2 stage catch for safety and I make them in bronze also.
This has my hallmarks and jewels vine in block letters around the ring. A vintage look made in my tiny studio here in NZ with care and attention to detail.
I ship FAST to all points of the planet! just take a look at my feedback to to see why folks keep coming back time and again to my store! http://www.etsy.com/people/jewelsvine/feedback
Outside diameter of ring is 13.5mm, thickness of ring is 3mm.