Smartcharge smart bulb 4 hours of light on power outage

Product Description Sudden power outages often leaves people helpless, grouping in the dark. Like where to put the candle and fire wood If the bright light can continue for sometime after a power outage it will be just fine. No Problem, this Smart Charge Energy Saving LED Bulb can make you no longer worry about grouping in the dark. It can determine if you are using the switch to turn off the lights or if a power outage has taken place. With the customized built-in sensor located inside the bulb, when there is a power outage two things happen: 1. If the bulb was already switched on in the house, lights remains for approximately 4 hours until power returns. 2. If the bulb had not been turned on, you can simply switch it on in order to obtain light for approximately 4 hours until power is restored Features: 1.Good CRI 2.Energy Saving - up to 80% energy saving over standard incandescent bulbs 3.Good Light quality 4.Long Life-span - approximately 40,000 hours, that's up to 8 times longer than standard incandescent bulbs 5.It is self-sustained - Its built-in 2200mAh lithium battery will take about six hours to recharge on its on when power is restored 6.Can be used as an everyday bulb 7.Can operate within 170-250V range Gives off 40 watts of light and only uses 5 watts .. 6400k of white light E27 normal socket I HAVE A FEW OF THEM