There are challenges with UV light water treatment that you should be aware of before purchasing:
UV light cannot remove all contaminants: UV can only remove waterborne microorganisms and cannot remove sediment, chlorine, lead, etc.
UV systems needs electricity to operate: Because UV needs power, it's not ideal for emergency water treatment or in back-country settings where power loss is common.
UV sterilizers do not improve taste of water: If your water smells or tastes bad, we recommend an RO drinking water system.
Prefiltration may be needed with a UV system: UV disinfection can only work if water is not murky. The "floaties" or suspended solids in water can block the light rays from reaching microbes in the water.