Equashield is a medication transfer device developed for the safe handling of toxic drugs. It prevents outside contaminants from entering the system and dangerous liquids from escaping. Instead of applying the conventional approach of using an external balloon to give the container an airtight seal, the system uses an encapsulated syringe barrel in which pressure equalisation is achieved directly. The syringe barrel is made of metal, which is more hygienic and provides smoother motion than plastic.