This 500mL bottle top filter from the Rapid-Flow™ series consist of a polystyrene housing with a 75mm Supor® machV polyethersulfone (PES) membrane. Filter securely screws onto glass media bottles with 33mm neck sizes. Allows direct filtration of liquid into sterile glass media bottles. CAUTION: Use only sterile bottles designed for use with vacuum. Always use safety shield during vacuum procedures. Filter features molded-in graduations and a side-arm with quick-disconnect tubing adapter. This product is not intended for use in direct patient care or diagnostic procedures. Blue collar. Material: polystyrene housing with a 75mm Supor® machV PES membrane. Filter capacity: 500mL. Fits Bottle Neck size: 33mm. Membrane diameter: 75mm. Pore size: 0.2µm. 12/Case. Nalgene® #: 595-3320.