Thermacell Mosquito Repellent Retargetable E-Series E55 creates a powerful zone of protection against mosquitoes. Easy to use, one button keeps mosquitoes away. Use this portable repeller on patios, decks or the cottage. Powered by a rechargeable lithium-ion battery with up to 5.5 hours of continuous mosquito protection per charge. No fuel to monitor and replace. Emits scent-free repellent that drives away mosquitoes. Repel mosquitoes without chemical sprays or lotions, or DEET. No smoke, flames or scents. Enjoy maximum protection in 15 minutes.