Nalgene MF75 Series Bottletop Filter, Polystyrene with Supor MachV Bottle 45mm Neck Size, 0.2 Micron, 150mL Capacity (Case of 12) Bottle neck size: 45mm; filter capacity: 150ml; pore size: 0.2m; membrane diameter: 50mm Material: polystyrene housing with a Supor machV polyethersulfone (PES) membrane Allows direct filtration of liquid into sterile glass media bottles Features a side-arm with quick-disconnect tubing adapter Blue collar