My Pure Plus reverse osmosis system has been working flawlessly for over 3 years thanks to these great replacement filters. Why does EVERYONE buy bottled water? I will never understand if there are such products on the market. Simple instruction that can be found on the web at any time in PDF format, easy to uninstall and reinstall. Takes several minutes for 6 months, maximum 10 minutes for replacement and maintenance within 12 months. I moved my system from the apartment I originally installed it in which took about 45 minutes and reinstalled it at the new location even easier as all the pipes were already cut and the system was simply assembled. , easy access to filtered water for cooking and drinking right at my sink. I'm healthier and noticeably less dehydrated ;-)