ThermaCELL Portable Mosquito Repeller. Built to be tough enough for any adventure the MR450 will quickly become an essential piece of gear. Thermacell Repellers have been evaluated by the EPA for safety and effectiveness. Specifications for ThermaCELL Portable Mosquito Repeller: Manufacturer: ThermaCELL Additional Features: No Active Ingredient: Allethrin Length: 11 in Height: 2.4 in Package Contents: ThermaCELL Portable Mosquito Repeller