The Long Budget Mortice Door Bolt is the perfect solution for additional home security. Steel Bolt This door bolt is made from steel and has a polished chrome finish.   Insurance Company Approval The mortice door bolt is commonly used to add extra security to pairs of double external doors, by either the use of a pair of bolts on the slave door or by a pair of bolts on both doors. The use of fixed turns on double external doors is not recommended, since releasing the bolts renders the lock inoperative. To satisfy insurance company requirements, the slave door of any pair of ...