The Uniden PRO401HH 40-Channel Handheld CB Radio is a mobile radio designed for use in the Citizens Band (CB) Radio Service. It will operate on any of the 40 AM frequencies authorized by the Federal Communications Commission (FCC). The PRO401HH delivers the convenience of a handheld CB radio with the security of knowing you have the longest range possible so you can always stay in touch. It features a superheterodyne circuit with Phase Locked Loop techniques to assure precise frequency control. It also includes a low-power setting to conserve battery life and a high-power setting so you can extend your range when needed.