Mottura Series 64 SERRABLINDA double-bit locks for security doors use a distinctive friction-knob system to operate the bolts.

The knob drives the locking bolts, while the double-bit key locks the mechanism. This operating principle sets Series 64 apart from other Mottura double-bit lock families.

The range includes rim and mortice SERRABLINDA locks in three-point and five-point configurations, with reversible latch for different security-door layouts.

Check the Mottura code, handing, fixing type, backset, centres and overall dimensions of the existing lock before choosing the replacement model.