Nalgene® bottle-top sterile filter units. filter capacity 150 mL, pore size 0.2 μm, fits 45 mm bottle neck. filter capacity 150 mL, pore size 0.2 μm, fits 33 mm bottle neck. filter capacity 500 mL, pore size 0.2 μm, fits 33 mm bottle neck. filter capacity 500 mL, pore size 0.2 μm, fits 45 mm bottle neck. filter capacity 1000 mL