The Boya BY-M1 Lavalier Microphone is suitable for all devices equipped with a 3.5 jack microphone input, such as smartphones, computer, audio recorders, amplifiers etc. The cable has a length of 6 meters and the microphone can easily be clipped onto your clothing, providing you with the freedom of movement. These features make the BY-M1 very suitable for use while walking, during a speech, for use during a lecture or even for hands free calling. The included LR44 battery does not need to be used when using the BY-M1 with a PC, laptop, tablet and smartphone. Only when used with certain recording equipment, such as audio recorders, the battery needs to be used. When used with a PC/laptop, the device must have a 3.5 mm combo port, for both headphones and microphone.