I'm not exactly sure myself. My husband had this and said it was extra. Asked me to put it up here on Listia. I was hoping someone more tech savvy than I would know
I had one similar, this looks like an SD card reader and a USB hook up for a camera, but it will for sure only work on first and second gen iPads. The size of the connecter has changed at the bottom I have a 4th gen and I need a new one badly! The hole now is so small, like a cell phone charger. Good luck! I'm a photographer and I like to do some editing for my website on my iPad so thats how I knew. Thought I would help sorry for butting in.