w4w mosquito repellent coils - outdoor use reaches up to 10 feet - each coil burns for 5-7 hours (three pack contains 12 coils & 6 coil stands) w4w w4w mosquito repelling coils helps to repel mosquitoes in confined areas outdoors. it is useful in places where there is little or no breeze. each coils burns for 5 - 7 hours and should be placed one coil for every 10 feet. these insect repellent should be used only outdoors. it is perfect to use for patios, porches, camping trips, pool areas, backyards and any outdoor activities to keep away those pesky bugs. read directions for use on packaging before using.