Klac system is a quick coupler for mini excavators from 1 to 9t. The engagement of the accessory is automatic, the unlocking is manual or hydraulic. Klac system is therefore a mixed quick coupler, with a "piloted" version.
The springs connecting the locking plate to the fastener, provide the engaging force. They keep the attachment in working position. The locking plate has safety latches on each side.

The safety latches (in red) automatically lock the locking plate to the quick coupler (the stops marked in green), when engaged. The accessory remain in its working position in all cases.
The locking plate can only be moved with the key.