Canada, Commonwealth. A Mark I Helmet, Named To Lieutenant Ridley Williams, Rcoc 1940 GTRexclude HJ Proficiency Pin - Silvered

HJ Proficiency Pin - Silvered bronze

the seminal SS insignia reference guide by John Angolia with Stan Cook

The reverse with a barrel hinge and vertical pinback meeting a round wire catch

Royal Naval Air Service Officer's Commission Document (inscribed "By the Commissioners for Executing the Office of Lord High Admiral of the United Kingdom of Great Britain and Ireland

Canada, Commonwealth. A Mark I Helmet, Named To Lieutenant Ridley Williams, Rcoc 1940 GTRexclude HJ Proficiency Pin - SilveredIn steel with a brownish green finish, non magnetic, with a 32 mm (w) x 30 mm (h) Royal Canadian Ordnance Corps insignia decal placed on the left side, the helmet with a steel strip protective edge at the opening and covered by a green and brown camouflage netting. Inside with a steel framed cradle supporting a black rubberized canvas liner, four rubber pads on the underside against the sidewall, cross shaped rubber pad held in place with a single