Beautiful, clear transparant plug made of glass. The faceted surface gives very pretty light effects (which are very hard to get on photo!).
Please note: these plugs have pretty large flares; if you've just stretched, or simply not have very flexible ear lobes, it can be wise to downsize.
An overview
(gauge - total size including flares):
3 mm - 4,5 mm
4 mm - 6 mm
5 mm - 7 mm
6,4 mm - 8 mm
8 mm - 10 mm
10 mm - 12 mm