Back-ups are pre-assembled quick-replacement groups composed of machine and/or size-group parts.

Back-up groups speed up maintenance operations and minimize machine downtimes in the case of breakdown, maintenance, adjustments or size-change.
The presence of back-up groups, which are interchangeable with those in production, considerably reduces non-production time.
It is sufficient to remove the group in use and to replace it with the interchangeable one, getting back quickly into production. The group removed can be overhauled while the machine is already in production.