Q:What is blister packing ? what is E.O.Gas ? why piercing jewelry need to do these work? A:E.O.Gas is a sterilize gas and use in every product that need be clean. Blister packing only can let the E.O.Gas enter and the bacterial can not enter.it let the piercing jewelry always keep clean before you use it.So your body will health. Why need to do these work ? Because safe and clean. we want all of our customers safe and health , then they will continue buy our jewelry :-)