As of 2013, most wireless networks use one of two radio frequency bands. These are not the only two bands, but are the most used. One of the bands is at around 2.4 GHz, and the other is at 5 GHz. Both of these have benefits and drawbacks: The 2.4 GHz band is widely used, and devices are usually cheaper. Microwave ovens, DECT telephones and other wireless devices also use the 2.4 GHz band, and sometimes cause interference which slows transmissions. The 5 GHz band has more frequencies and usually less interference, but there are more rules for using it. In some places, the 5 GHz band may not be used outdoors. Because fewer devices use the 5 GHz band, devices that do are often more expensive.