yes it is smooth with no prongs just a flat meta strip

Ribbon cables have either a strip type plug on the end which plugs into a row of socket pins or alternatively a flat smooth end that pushes into a low profile socket. If the end looks as though its a row of flattened wires glued onto a flexible plastic base then its the latter, so you look out for a thin strip type socket on the adjacent board, and if seen close inspection show show that its got a thin slot in the middle, this being where the ribbon pushes into. I would lightly wipe the end of the ribbon connection with Vaseline or similar to help ease it into the socket, as should you accidentally lift one of the tracks its a very difficult job to get it to stay in position again.