K98 bayonet frog marked Gustav Sudbrack 1940

Textbook early war K98 bayonet frog constructed from brown leather which had been blackened. The frog is beautifully marked Gustav Sudbrack, Bielefeld 1940. The frog seems to have been brown leather originally but the front has been blackened due to regulations. The frog is in good used condition and would easily match any bayonet!