A conveyor belt brings the boxes towards a starcross unit that takes and inserts them into a bucket of the toothed chain. Each box is brought until a rotating group by the chain and inserted between two plates by a pusher.
The rotating group is composed by six orbital sub-station composed by two plates laid one on top of the other and free to rotate on their vertical axis while the principal group rotates. A second group unwinds the seal-band. A third one unwinds the coil of the neutral part. The different speed between the external circumferences of the box and the rotating drum allows the application of a strip of seal-tape well taut and centred.