These long life compact fluorescent CFL helix spiral light bulbs energy savers give a light output equivalent to a 150W light bulb yet consume just 30W of electricity. Features a ES-E27 Edison screw (27mm) base/cap.Featuring flicker-free instant start electronic circuitry, they give off a warm, yet bright white light and are ideal replacements for the higher power filament light bulbs. Not suitable for dimming.Need more help in choosing a suitable light bulb? Read our guide Choosing Compact Fluorescent Lamps