A seal prevents or limits unwanted transfer of product from one container to another.
Seal Seal A seal prevents or limits unwanted transfer of product from one container to another. Seal is used as superordinate term for all types of sealing elements. Pressure/vacuum relief valve Pressure/vacuum relief valve is an umbrella term that includes pressure or vacuum relief valve as well as pressure and vacuum relief valve. is used as superordinate term for all types of sealing elements.