Silicone Earskin (Clear)
These are thin-walled silicone eyelets that make your piercing look like a round, open hole. They should not be used to stretch with, as they may be unable to keep a freshly stretched piercing at the new size. The flares on these are not like regular plugs where they come out and around your lobe--they are extremely small flares that barely come out of your piercing.
Jewelry is measured through a gauge system (see chart below). The higher the gauge number the smaller the wire is. A standard "earring" is usually 20 gauge. Jewelry gauges/sizes can vary between manufacturers. There is no universal regulation on companies to make a standard size in body jewelry. A big part of this is that some jewelry is made overseas and measured in millimeters. And in the USA jewelry is measured in inches/gauges. So many times jewelry can be anywhere from .5mm to 1mm different.