There are three frequency bands most commonly used for unlicensed operation. These are 260 – 470MHz, 902 – 928MHz and 2400 – 2483.5MHz. In the 260 – 470MHz band, the FCC considers not only RF performance issues but also issues of application, such as what the data being sent originally consists of and what the intended function is. The primary application in this band is the manual operation of remote control devices, so narrow band devices are normally used here. Other applications are possible here, but they are subject to restrictions. Part 15.231 should be reviewed to ensure that an application will be allowed in this band, paragraphs A-D specify the requirements for manual activation of command and control signals, paragraph E applies only if A-D do not apply. In the 902 – 928MHz and 2400 – 2483.5MHz bands a user is allowed to transmit any analog or digital signal they wish so long as the stipulations governing allowed power output, harmonics, and occupied bandwidth are met. These bands are used for narrow band and spread spectrum devices.