The USWF-4CR2 Contractor Series UV disinfection system is a reliable, economical, and chemical-free way to control microbiological contaminants including E.coli, Cryptosporidium and Giardia lamblia in residential and light commercial applications up to 15 GPM. This system combines the power of UV disinfection with an integrated 20"x4.5" sediment prefilter. Because UV light only travels in a straight line any shadow or obstruction will reduce its efficiency. The integrated sediment prefilter ensures suspended particles like silt and sand that can block the UV light are removed for optimal system performance. Designed with ease of operation in mind the system uses a bayonet style UV lamp connector which allows for quick lamp changes without tools, and the prefilter housing has a built-in drain plug to make changing the filter and quartz sleeve a breeze. This UV system utilizes a low pressure, high output UV lamp rated for 10,000 hours of continuous output, housed in a commercial grade axial flow UV chamber made from 316L grade stainless steel which offers better durability and corrosion resistance compared to the 304 grade stainless steel chambers used by many other brands. The controllers for the USWF Contractor Series provide both visual and audio lamp out indicators in a splash-proof case. The ballast in the controller is also fully potted to further protect against possible water damage and to improve heat dissipation. By purchasing a USWF-4CR2 you're not only getting a high quality UV disinfection system, but also peace of mind that the water in your home will have an extra level of protection.