A vacuum coating unit having a pair of side by side transport devices for transporting substrates in a transport direction. Each transport device includes at least one first endless conveyor running in the transport direction and having a conveying element guided around at least two guide rollers or pulleys. The conveying element is located at a distance from a guide device extending in the transport direction parallel to the conveying element in such a way that the ends of the substrates can be introduced into the gap between the conveying element and the guide device of the transport devices and can be moved in the transport direction by the displacement of the conveying elements.