Woods LampThis Woods Lamp is a single function machine and uses UV light to diagnose skin conditions. Bulb is 4 watts and uses 4 bulbs that are included. Also comes with a cloth sleeve to protect unit when not in use. Helps Detect: Ringworm, Fungus fungal infections, Head Lice (Nits), Corneal Scratches (When used with fluoroceine dye), Foreign bodies in the eye, Vitiligo, Gemology & Mineralogy, Blocked tear ducts, Acne, Erythasma, Tinea versicolor, Microsporum