Feature 1----Interference Eliminator Code Interference eliminator codes help minimize interference by providing you with a choice of code combinations.To set the code for a channel: 1.Press MENU key until the code starts to flash. 2.Press to select the code 0-99 or 99-0. 3.Press PTT key to save the code setting. Feature 2---Locking the Keypad 1.To avoid accidentally changing your radio settings,press CALL key for 3 seconds or until CALL key displays and there is a ''beep'' tone. You can turn the radio on and off, you can't adjust the volume, menu, and monitor channels. All other functions are locked. 2.To unlock the radio,press CALL key for 3 seconds or until CALL key is no longer displayed. And there is a ''beep'' tone. Note:When locking, only the PTT key and CALL key are valid. Feature 3---To set a call tone 1.Press MENU key button until c r 08 icon appears.The current call tone setting will flash. 2.Press (UP/DOWN) to change and hear the call tone. 3.Press PTT key to save. Feature 4---Voice Operated Transmission(VOX) Transmission is initiated by speaking into the microphone of the radio instead of the pushing the PTT button. 1. Press the MENU key 3 times to enter the voice control function setting. 2. Voice control level 1-3 optional (lowest level 1, highest level 3, OF is off) Note:Note Level ''N''(OFF) disables VOX Levels 1-3 set the sensitivity of the VOX circuit use level 1 in quiet environments,and use level 3 in very noisy environments. You can find the appropriate sensitivity level by speaking into the microphone. Classification : Intercom Talk Range : 3km Item Type : Toy Walkie Talkies Age Range : > 3 years old Gender :Unisex,Boys and Girls Battery:4 AAA batteries (not included). Features :Educational Toys,Gift for kids .Birthday gift