Replacement Whirlpool dual stage pre/post filter 2 pack (fits systems WHADUS5 & WHED20)Certified to reduce numerous contaminants including chlorine taste and odor, sediment, cysts, lead and chemicals6 month filter life - replace your systems pre and post filter every 6 months. It is essential to change your filters on time to ensure your system is working properlyUltraease filter replacement - change filter in seconds with just a quarter turn no hassles, no mess, no need to turn off your water supplyQuestions? Call 1-866-986-3223 for more information or text FILTER to 444999 for filter change reminders.