IPAK Gard(R) 3-5 pretreatment pack H provides optimal protection of the reverse osmosis (RO) membrane for hard water, improving your system's performance and extending its lifetime. For use with Milli-Q(R) IQ 7003, Milli-Q(R) IQ 7005, Milli-Q(R) IX 7003 and Milli-Q(R) IX 7005 water purification...