dmc slot

what fits in the Dell M6600 1x1 DMC slot? I have a dell m6600 with an Open DMC slot. sakti4d slot login I already have 2 1TB Sata ssd drives installed, 1 msata 256GB SSD, Wifi and Bluetooth, 32GB Ram, 2 extra 3 0 USB slots in the 54mm express card slot, for a total of 4 USB 3 0 slots, but have no idea what the 1 inch x 1 inch DMC slot is for, or what the acronym