Refills are where they hook you. A refill package that contains one propane cartridge and three pads is about twelve hours worth. The generally run $5-$7 depending on where you get them from. There are packages that will give you four refills (48 hours worth) for around $20. My wife spotted some at a local grocery store last year that they were trying to get rid of and bought them for $1.50 a box.