Product : Stegayoung Forest Anion Light Bulb (Energy Saving Bulb) Description Unlike any light bulb you know, Forest Anion Light Bulbs feature a negative ion generator that emits negative ions into the air. These negative ions neutralize positive ions that can be present in the surrounding. With Forest Anion Light Bulbs, those nasty airborne particles like Smell, Odour, Smoke, Fumes, even harmful chemicals etc. will be thoroughly eliminated, leaving the air cleaner, fresher and healthier. Technical Specification Voltage : 110-120V / 220-240V Wattage : 15W, 20W, 23W, 50W Lamp Type : Spiral / 4U type / FL Tube Light Color : Daylight(White Light) & Warmlight(Yellowish) Average Life Span : 10,000hrs Base : E14, E26, E27 & B22 Anion count Measurement : 985,280/cc Antibacterial Test for Escherichia Coli : 93.2% in 3 hours Ozone Test : Ozone Free (According to World Health Organization Guideline) Certification : CE, ISO, FCC, RoHs, UL , cUL , Singapore TUV / PSB & Lab Test Reports for Ozone & Bacterial.