A transport unit for transporting printed circuit boards along a direction of transport within at least one zone of a soldering system, in particular a reflow soldering system, characterized in that a base part is provided with an output shaft that can be driven, and with at least two output wheels which are rotatably coupled to the output shaft, in that at least two drive parts which can be releasably fastened on and removed from the base part are each provided with a drive wheel in such a manner that the drive parts have drive rollers which are rotatably coupled to the drive wheel, and which act on the printed circuit board to transport the printed circuit board through the zone, and in that, when the drive parts are fastened to the base part, each of the output wheels is in engagement with the associated drive wheel.