It effectively discourages mosquitoes from the 21m² protection area. You can take the MR300 mosquito repellent with virtually anywhere to frighten disturbing mosquitoes before being harassed. The MR300 is the latest Thermacell mosquito repellent device that boasts new and advanced features. The new features include: quiet power on, multi -directional evaporator grid, improved ergonomics and accessory gathering system.