They're kinda shaped like a rectangular box, a couple inches thin and fits in the palm of your hand. On one side is where you put the Chip, and on the other is a slot. The slot goes into a special wristband/armband/belt (recipient's choice most of the time) from which the Deck draws a bit of blood. That in turn activates it. Is that a bit closer to what you were hoping for?

And yeah, F does pretty much nothing. Still better than nothing though ^_^;