Travel Smart by Conair Thermacell 2pc. Refill Cartridge<div style="text-align: left;"><strong>[Product Information]</strong><ul><li class="showHiddenFeatureBullets"><span class="a-list-item"> Lasts for approx 2-3 months of normal use </span></li><li class="showHiddenFeatureBullets"><span class="a-list-item"> Approximately 12 Gram of gas in cartridge， 2 - 2.5 Gram per hour， for total 6-8 hour use </span></li><li class="showHiddenFeatureBullets"><span class="a-list-item"> Two cartridges per package </span></li><li class="showHiddenFeatureBullets"><span class="a-list-item"> No messy refilling </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/31X%2BFKoZcfL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31oEucn7DuL.jpg" noproxy>