EMD MILLIPORE UFC501096 Amicon Ultra Centrifugal Filter Unit with Ultracel-10 Membrane, Clear, 0.5 mL Volume, 1 sq. cm. Filtration Area, 10.8 mm Diameter x 49.9 mm L: Amazon.com: Industrial & Scientific
Merck Amicon™ Ultra-4 Centrifugal Filter Units Ultra-4; w/Ultracel-3 membrane; 3000 NMWL; Dia. x L: 17.2 x 73.4mm Merck Amicon™ Ultra-4 Centrifugal Filter Units | Fisher Scientific
Millipore UFC901024 Regenerated Cellulose Amicon Ultra Centrifugal Filter Unit with PLGC Ultracel-10 Membrane, 15mL Capacity, 10kDa NMWL, 29.7mm Diameter x 122mm Length, 7.6 sq cm Membrane (Pack of 24): Science Lab Centrifugal