PS:If you get the equipment does not work, you should first charge it. All the equipment has been tested manually, and each device can work normally. If the product you get doesn't work. You need to check the following two points: First, the device can not be turned on, this is the battery is out of power, please charge the device, and then long press the power button to turn on, the device can work normally. Second, if the equipment can't work as expected, first of all, confirm whether there is no electricity! Test method, test whether the machine can be turned on! If it doesn't work, please charge the device. However, if you can turn it on and hear the sound, check your Jack and connection. Make sure that the jacks are plugged in and connected correctly. If this does not make the device work, it is incompatible, please replace other devices. Features: 1.Different Sound Changes: This Hand-held Voice Changer has at least 7 different sound changes, Male to female, Female to male, Lolita, Robot, Magnetic, Queen, Minions, Optimus Prime. And you can use the "Fine tuning" button to adjust each sound, making you to get more different sounds. Perfect used for making calls and entertainment with friends, voice change of online games, etc. It is a must-have device. 2.Built-in 8 Sound Effects: It comes with 8 fun sound effects, you just need to press the button of each sound effect to have interesting sound effects. The ten sound effects are Cold field, Count down, Show up, Applause, Kiss, Laughter, Cheer, Surprised, and it also provide rich analog scene modes, such as KTV, DJ, Phonograph, Studio. Specifications: Material: Plasti c Color: black Mode: 12 Fixed sound effects: 9 Signal to noise ratio: 106db Charging input: DV 5V/1A Battery energy: 3.7wh Battery: built-in battery Dynamic range: 106db Battery failure: about 3-4 hours when full.