I happened to insert my micro SD card in the ST16S and it missed the proper slot opening. It fell into the controller and was rattling around, so I decided to open up the back. It is kind of tricky getting the rubber grips in the small grommet holes, but with some persuasion I got it all back together. I didn't really need to take the whole back all the way off to get the sd card out. All I had to do was loosen it up and let it fall out of the top after I just opened up enough gap. I understand other H flyers are finding out that the SD card opening is quite wide and you have to be careful to insert the card in the slot and not do what I did.