Shoo Away is a safe, chemical-free way to keep flies off your food. Effective outdoors it is great for picnics, BBQ's and camping. Shoo Away uses patented hologram based technology to keep flies away. The Shoo Away holograms scatter light which flies see as "movement", hence the range of effectiveness is wider than the soft-touch blades. Each Shoo Away has an effective range of about 70-100cm diameter.