This LED bulb uses only 8 watts, it is energy-efficient and an ideal replacement for a traditional incandescent or CFL bulb. The Nebo Emergency Bulb functions like a standard LED bulb, fitting most lighting fixtures. Its rechargeable battery stays charged and can provide light for up to 12 hours during an emergency. Twist the light into the socket of your fixture or lamp. When you turn it on, it will begin charging the internal battery. By twisting the included power cap onto the base of the bulb, it can be used as a portable handheld light or hung from the integrated hanging hook. The Nebo Blackout Backup Emergency bulb offers peace of mind.