40w equivalent, a19 led light bulb, 5000k daylight(natural white), e26 standard base, non-dimmable, 450lm, ul listed, 4-pack energetic smarter lighting q:are the bulbs mercury free?<br> a:yes. all led bulbs are mercury free.<br><br> q:how long does the bulb last?<br> a:life hours is 15000 hours.we have had ours for almost two years now and still good.<br><br> q:will this work in garage during winter months?<br> a:yes, led likes cold. extreme heats they don't like because they are electronic.<br><br> q:is there a buzz or any other sound with these?<br> a:nope no buzz/sound when bulb is on. bulb has no wait time to warm up either.<br><br> q:are these bulbs hot to the touch when turned on?<br> a:not at all - no comparison to an incandescent bulb.<br><br> q:can these fit in household lamps right?<br> a:yes.they are standard shaped bulbs, (a19), with a medium, e26 base, (screw diameter and threads). they are made to fit just like a standard incandescent bulb.<br><br> q:are these bulbs instant on, or do they have a lag from the time you flip the switch?<br> a:yes.they are instant on and are not affected by cold.<br><br>q:are these led bulbs non-dimmable?<br> a:yes,they are non dimmable bulbs.<br> q:are these a19 led bulbs ul certified?<br> a:yes,they are ul certified.<br>