The Fortessa Rounded Standard Escutcheon Polished Chrome has a 51mm diameter. This is to be used with a 3 or 5 lever mortice deadlock or sashlock; some of these can be found in the related products or in the Hinges, Locks & Latches category. This escutcheon is made from zinc alloy & has a polished chrome finish - it is to match the Achilles handle in the Fortessa range. Other Variations It is also available in a satin nickel finish & this can be found in the related products.