paid 400 cnd works well on helmet ,havent tried mp3 music yet ,and have it mounted on h bars drilled a hole in one of my hand gaurds and screen goes in tank bag were i can see it ( clear map pouch) lens adjusts easily there and a glance tells me its still pointing were it should be ,gps is on bars,and touring screen makes other mounts akward.cant wait to get road trip footage it says 6 hrs of recording ,camera lens is 1 1/8" round and 2 1/2 " aprox long its fully water proof ,the digital recorder part isnt has to be in coat or tank bag ........guys use em on sleds around here for snowmobile season (am testing hand gaurd mount afternoon tomorrow)still have to hook up battery lead ,running on batery pack 8 double a