The later versions first generation Milli-Q water system came with individual filter housings and have a beige hinged top and a beige meter that can be remote mounted . These systems were configured with 4 and 5 housings and used Polypropylene interconnects on the housing making them suitable for many or todays critical applications. These systems could also be configured to remove pyrogens using a ultrafilter. System with ultrafiltration have a drain valve at the bottom of the far right filter housing. In this section you will find all of the replacement filters you need.