Made of water resistant material to use in harsh environment. 22-channel operation with up to 24-mile range, longer range communication in open areas with little or no obstruction. One call alert tone notifies you of incoming calls within your group. Dual-power options; uses 4 AAA batteries (not included) or rechargeable lithium-ion battery pack (included). HI/LO power settings let you adjust transmit power and conserve battery life. Automatically checks channels for activity. Silent operation turns off all tones for quiet operation. Keypad lock, locks in your selected settings. Auto squelch removes annoying background noise.