The boya by-bm3032 is a shotgun directional microphone for your video camera which is ideal for general sound recording. the by-bm3032 is compatible with dslr cameras, camcorders and audio recorders. for high reliability, this directional microphone is made of high quality plastic and has a built-in shock absorber. this eliminates unnecessary vibrations and therefore background noise. There are three sound levels to choose from during the recording: +20db, 0db and -10db. +20db amplifies softer sounds; -10db, on the other hand, makes loud sounds less likely to cause over-amplification. in addition, this directional microphone features a low-cut filter, which filters out lower-frequency sounds. the by-bm3032 comes with a pop cap that minimises background noise such as wind noise. this makes it possible to use this directional microphone in different situations. Usage by-bm3032 To use the microphone, insert two aa batteries (not supplied). this allows you to use the microphone for up to 30 hours. then attach the directional microphone to your camera using the 1/4" threaded connection or the hotshoe. using the supplied 3.5mm output cable, you can connect your camera to the microphone. When you briefly press the button on the left, you can adjust the low-cut filter in 0hz, 75hz and 150hz. you can also increase the high frequencies by 5db by pressing and holding the same button for a long time. the led light will be on continuously. if you want to turn this off, press and hold the button again. Just like the low-cut filter, you can set the sound levels in three different levels: -10db, 0db and +20db. you can set this with the button on the right side. if you hold this button down for a longer time, the level will be lowered by 10db. Automatic on and off function When you press the power button, the microphone will be turned on. pressing it again for three seconds will turn on/off the automatic power on/off function. when this function is on, the led will flash briefly three times. if the function is off, it will flash only once. you can use this function when your microphone is always connected to a camera. this eliminates the need to turn the microphone on separately from the camera.