These smaller Sterling Silver Hanger Bails are designed for use with components with a large center hole, such as many styles of donut beads. Overall size is about 14x4mm. Loops at the top of the bail have an opening of about 3x2mm. The back of the finding is narrower than the front (about 2.5mm), but your component must have at least a 4mm hole to allow the top loops to fit through. Measurement within the hanger is about 7.5mm and maximum thickness is about 4mm. The picture shows this bail with a 20mm round donut for an example of one type of bead that will fit within. Sold individually.
These donut hangers are designed for donuts with a fairly small dimension from the edge of the center hole to the outer edge. The hanger has room for about 7.5mm of width. Donuts that are wider than that, or thicker than 4mm will fit in the hanger, but the bail may not close enough to allow the loops to line up. Since they are made from Sterling Silver, the bails are fairly soft and can be formed to fit around your pendant to some extent.
While these hanger bails are designed to open wide enough to slip the donut over the loops, repeated opening and closings or opening the bail past about 45 degrees can cause the material to crack.
