Perfect Fit: Compatible with Filtrete* System 4US-MAXL-S01and 4US-MAXS-S01. Healthy Choice: GLACIER FRESH Filter Compatible with 4US-MAXL-F01. Any unpleasant taste or odor are completely removed, while health-benefiting essential minerals are kept. Filter Life: It is recommended that you change the filter either every 6 months or every 300 gallons to achieve optimum performance. Exquisite Design: Easy to install and operate. You can enjoy maximum water filtration without taking up a lot of cabinet space. Tips：Please be sure the part number is an EXACT match for your system before ordering.