Haier is a well-known home appliance giant among Chinese consumers, one of the drafting units of the national standard "Water Efficiency Limits and Water Efficiency Grades of Reverse Osmosis Water Purifiers", and the first batch of brands that have passed the A-level water efficiency certification.

Among Haier's pre-filters, the HP series product line is the most popular. Among them, HP15 is cost-effective, it is equipped with a pressure gauge and a flushing time recording scale, using a 40 micron 316 stainless steel filter, the double-sided scraping technology of the filter screen is an exclusive patent, and it can also clean the bottle wall, and the price is about 600 yuan.

Another product line is the PF series, its high-end representative HSW-PF9, with a flow rate of 3 tons per hour, with an exclusive patent, the copper body can be isolated from water contact through the lining isolation layer, the filter bottle does not contain bisphenol A, to avoid pollution, to ensure the health of the water, to support 360-degree universal installation, not limited by the installation direction, the price is about 1,000 yuan.

In addition, it is also one of the few products with a timed automatic flushing function, and like Midea's Beverly QZBW20S-16, users can set 7, 15 or 30 days of automatic cleaning, of course, it also requires an external power supply and sewage pipe.

Although the low-end PF2A does not have a water pressure gauge, it also supports a 316 stainless steel filter with a large flow rate of 3 tons per hour and an accuracy of 40 microns, and supports siphon backwashing and double-sided scraping, priced at about 300 yuan, which is quite cost-effective.