µStar units have a bi-directional flow pattern that eliminates the priming and air lock effects of conventional syringe tip filters. Filters have a cellulose acetate membrane in a polyvinyl chloride (PVC) housing. Utilizes all of the membrane surface area for a working volume up to 100 ml while minimizing fluid retention to less than 30 µl with an air purge. Integrity tested with a maximum operating pressure of 100 psi and is designed for sterilization and clarification of aqueous solutions. Sterile, certified non-pyrogenic. Individually packed.