I found this while going through my deceased father’s belongings. Opened it measures 8 1/2" from tip of knife blade to tip of button hook. Closed 3 1/2" long/ Front and back are hallmarked as is the hanger and the ring. At the base of the large blade, one side is marked Drew & Sons and the other side Piccadilly Circus. Hallmarks on one side are, crown, lion passant, letter “F”, Letters WM&S. On the other side, Lion Passant, Letter F, Letters WM&S. I cannot read the marks on the hanger and the ring as they are too small. I am assuming it was made later 1800-early 1900’s.
As you will see, the condition is not that great. More of a sentimental value, but I would be interested in what it would be worth in today’s market.