Ultrafiltration units are disposable capsules for use in conjunction with syringes to concentrate very small samples. These devices are used extensively for protein concentration and provide an energy-efficient alternative to traditional methods of membrane filtration with a consistent level of quality. The clear housing of these units enables visual confirmation of the filtration process in effect and when filtration is complete. Ultrafiltration units are easy to disassemble so that concentrated samples and filtrates can be analysed.