Check the listing for details. Vintage Aston & Mander & Co Est. 1789 drafting/navigational instruments w/case. Listed at 400.00 USD. A.M stamped and 1939 dated; A.M. marked Dargue Brothers Halifax ebony and brass 6” parallel rule. The case has brass fittings and lock but the key is absent. The lid is marked with 'A.M.' King's Crown and 1940 date.