Proster Walkie Talkies Rechargeable 16 Channel 2-Way Radios CTCSS DCS with Original Earpiece and USB Charger 3 Pair (3 Pair Walkie Talkies) UHF 400-470MHz, 16 Channels --- Enables to connect each other in a long range of about 2 Miles (Max in OUTDOOR Open Field, it exactly depends on your surroundings). DCS and CTCSS Function --- It can shield external interference signal and reduce noises. USB Charger --- (Your outdoor partner) Charging even you are outside with car charger/power bank.Most of your USB Charger is suitable for this convenient charging, You may use a PC charger, Car charger, mobilephone charger to charge it. Build-in LED Emergency Flashlight --- Expose yourself location to ask for help in emergency. Wide Application --- This walkie talkies are perfect for security guard, supermarket connection, construction area or field/outdoor adventure and survival, biking and so on.