ThermaCELL Mosquito Repellent The ThermaCELL is a great alternative to citronella candles and other old-fashioned methods for keeping mosquitoes away. Just fire up the ThermaCELL Portable repellent and enjoy your next outing in bug-free peace. A butane cartridge heats a chemically treated repellent mat that keeps mosquitoes out of a 225-sq.-ft. area for up to 12 hours. They're cordless, portable and require no messy wax. The Olive drab Portable Appliance includes three repellent mats and one butane cartridge. Works best under calm conditions. 15 minute warm up time. There are 2 refill kits available: The 12 hour Refill Kit includes three repellent mats, and one butane cartridge and the 48 hour Refill Value Pack includes 12 mats and four butane cartridges. Plugsplus your Sporting Goods Alternative. These items are shipped by Parcel Post because they contain butane. Shipping time is 7 to 10 days.