Whatman 4 mm syringe filters are designed to provide clean filtrate from small volumes up to 2mL. They are available in a variety of filter media choices with a polypropylene housing and utilize the most advanced methods and design features available today. This level of engineering provides for the finest disposable filtration devices possible. Sterile, non-pyrogenic product is sealed in a medical grade, clear blister pack, radiation sterilized and sealed in their own protective shelf pack.