Glacier Fresh Replacement Filter For Maximum Under Sink, S01 System,2 Packs Product Features 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. Shipping: Shipping is complimentary within the lower 48 US States. We Do Not Ship to PO/APO Boxes, HI or Alaska We Do Not Ship Outside of the Continental US All items ship within 24-72 hours of Payment For large items that require Freight shipping a valid phone number is required to call and schedule your delivery Terms of Sale and Feedback: Feedback is extremely important to us and If you are satisfied with our transaction, please take a moment to leave Positive Feedback. YOUR Satisfaction is our #1 Priority! If there are any issues, PLEASE contact us BEFORE leaving a neutral or negative rating so that we may resolve any concerns. We PROMISE we can make you happy if you give us a fair chance. Returns / Concerns: All items qualify for returns within 14 - 30 days of receipt. Buyer is responsible for return shipping on any item that is not damaged Please be sure this is an item you want before making your purchase. Customer Satisfaction is our TOP priority! All items are IN STOCK at time of listing. Inventory changes constantly and it is impossible to maintain a perfectly accurate count of all items. Please do not penalize us if we have to issue you a refund! Thank You For Your Business!