Disposable Inserts for Regular 3 mm Studs are to be used with the disposable ear piercing systems which are required by law in Ontario. With every pair of studs you are required to use a new set of disposable inserts (which are NOT to be re-used, single use only). Disposable inserts are colour coded for your convenience. White inserts are designed to be used with regular 3 mm studex studs. These inserts are supplied as a package of 12 sterilized inserts.