You instantly know you are in hand of a top quality product the moment you hold the box in your hand. The item is simple and very little parts to it.It comes with the microphone, wind muffler, and a battery. I'm so used to receiving products and having to purchase my own batteries this instantly was a winner for me. It fits into any dslr with the hot shoe on top and see no issue with it's fit. I have a gopro that i tend to use for all video needs but occasionally end up using the dslr for short clips if it is already in hand and that moment comes. The microphone appears to me to have a decent range. I can't say for sure if the 20 metres it claims is accurate but what i did notice is how much clearer the noise/voices were compared to without. Not had a lot of trial with it other than to test it works and a little play around but it does make a difference.One thing i will note is that in the heading it does come across as though it would be useable with the gopro hero 4...not sure how this would work with the standard jack plug when there isn't one of these on the gopro, however would maybe be a little large for that anyway so not looked into it.As an addition to my camera accessory pack it is a welcome and pleasantly surprising little item. Great product and would recommend