In 4 Watt 6 Inch Category, Philips TUV 4 Watt AND 8 Watts are available. The Customer can select either one of them while placing the order. This UV Lamp emits the UV - C type Radiation of frequency 254 nm (Nano Meter), which is more than sufficient to kill any biological germinations of virus, bacteria, micro-organisms etc from the feed water supply. This UV Lamp is compatible with Water Purifier machine of Aquaguard, Aquasure, Havells, Livpure, HUL Pureit, Hindware etc. Philips make lamps are originally factory fitted in Water Purifier machines of these brands. Philips make UV is manufactured Poland.