The CF Drive connects to the Beeb's 1MHz Bus via a 34-ribbon cable as shown here. There's a handy warning for the unitiated as well as the power connector. It needs 5V and about 300 milliamps - that's a lot less than a 20MB Winchester which needs more like 2,500 milliamps!
That's your lot - no, no, I'm not opening it, I might break it! Maybe another time...