The boya condenser shotgun microphone by-bm3031 is a supercardioid condenser microphone, which is ideal for general sound recording in your studio and on location. the by-bm3031 is compatible with dslr cameras, camcorders, audio recorders and more. for high reliability, this directional microphone is made of abs material and equipped with a built-in shock absorber. this eliminates unnecessary vibration and thus background noise. During recording, you can choose between three sound levels: +20db, 0db and -10db. +20db amplifies softer sounds; -10db, on the other hand, reduces the likelihood of loud sounds leading to overloading. in addition, this directional microphone has a low-cut filter, which filters out sounds at a lower frequency. in addition to the foam windscreen, a fur windscreen is also included, minimising background noise such as wind noise. this allows this directional microphone to be used in different situations. Usage by-bm3031 To use the microphone, insert two aa batteries (not supplied). this allows you to use the microphone for up to 120 hours. then attach the directional microphone to your camera via the 1/4" threaded connection or the hotshoe. with the supplied 3.5mm output cable you connect your camera to the microphone. by using the left slider you can switch off the microphone and make a choice between switching the low-cut filter on and off. by means of the slider on the right you determine the desired sound level. you can also listen to sounds in real time; you can do this simply by connecting your headphones to the built-in headphone jack.