The service life of CF filter is 6-12 months, the service life of RO filter is 12-18 months, only costs 0.2 dollars per day. The purified water of CF and RO filter is equal to 12,000+ bottles water (the bottle is 11.2 oz).Note: Q3-600 has filter replacement reminder function. When the life of the filter expires, the indicator light of the filter will start to flash, reminding you to replace the filter in time. The sealed under sink water filter is made of durable materials, which will not break or leak. The integral design eliminates harmful impurity from breeding, which also allows you to get rid of replacing bottom cap. Replacement can be completed within 2 seconds with a single twist and no need to use any tool. Providing you with the eaisiest way to install without disassembly.