Era Fortress Mortice Sashlock Brass 63mm Option:Brass 76mm The British Standard High Security The British Standard High Security Mortice Lock meets the new BS 3621:2007 standard Features a 20mm bolt throw * Interior & Exterior Material: Zinc Alloy Fixings included 10 year guarantee and warranty which meet the exacting demands of the insurance companies and the police 1000 key variations High security levels are delivered by a 20mm bolt throw on every lock All locks have hardened steel plates to resist drilling False notching in levers resist lock picking Interior & Exterior Material: Steel & Zinc Alloy Fixings included 10 year guarantee and warranty The British Standard High Security Mortice Lock meets the new BS 3621:2007 standard