Consisting of a metal claw, which holds together the sanding aggregate and machine base. It automatically unlocks the sanding aggregat if the door of the machine housing is opened and locks it automatically if the door of the housing is closed. In this way the automatic aggregate locking enables a quick belt change.

Machine types with automatic aggregate locking

Standard equipment in the following series (2003):

• Bütfering Diamond
• Bütfering Lucky
• Bütfering Special
• Bütfering SWT from type 300 series up

Similar systems from other manufacturers

• Quick-lock, supplied by Costa Levigatrici
• ALS by DMC