Abstract: An endless carrier for a packaging machine includes leading clamps which are mounted on one endless chain and trailing clamps which are mounted on another endless chain. The chains are independent of each other such that the distance between trailing clamps and leading clamps can be adjusted simply by moving the position of one chain relative to the other. The present invention may be incorporated in a newly built packaging machine or a retrofit kit for replacing the endless carrier of a preexisting packaging machine. To provide for ready adaptation of the distance between leading and trailing clamps, one of the sprockets connected to the drive shaft of the packaging machine can be a phase sprocket capable of being fastened and unfastened to the drive shaft such that the chain can be rotated simply by rotating the sprocket relative to the drive shaft to reposition the endless chain relative to the other endless chain.