Be sure to check them all on arrival! Three lightbulbs didn't work at all. Revain was great and got my money back. Also, I found that the lightbulb I put in the wax heater doesn't melt the wax like the original lightbulb does! After further research, I found out that Scentsy uses a 15W 130V bulb (for plug-in night light modules) and these bulbs are only 15W and 120V.