Designed for gentle cross flow filtration of small volumes ranging from 500 µl - 60 ml, disposable MicroKros Hollow Fiber Modules are the first efficient and practical tangential flow filtration device for R&D volumes in the laboratory setting. While MicroKros modules are typically operated by a peristaltic pump, these devices also offer the unique advantage of manual operation for quick and convenient separations for small volumes. Concentration utilizes two retentate syringes connected to the luer inlet/outlet ports to pass the sample back and forth through the membrane lumen while a third syringe collects the filtrate by way of one of the side-ports. In diafiltration, a fourth syringe can be used to either supply more sample for concentration or buffer for diafiltration via the luer T connector.