3540 Series Bolt Suitablity Table Bolt Suitability 22 mm (3540) 28 mm Hook (3541) 35 mm (3542*) Fabricator Mounting Yes Yes Yes Standard Mounting Yes Yes Yes Timber Mounting Yes Yes Yes Extended (30 mm) Backset - Yes - Latching Strike - Yes - Security Strike - Yes - *Note: 3542 is not suitable for sliding doors.