Vintage Hammer Brand Switchblade Folding Knife

What type of Knife is this? It was with my grandpas stuff, no idea where its from. : r/knives

VINTAGE HAMMER BRAND USA CRACKED ICE SWITCH BLADE BUTTON KNIFE (RV97)

AIK - Adams International Knifeworks

Switchblades- www.bigswitchbladeknife.com likes this Vintage pocket knives, Switchblade knife, Stiletto knife

Vintage 1945-1955 Hammer Brand Single Blade Folding Pocket Knife 2170537/2281782

Kraft Auction Service Auction Catalog - 45th Anniversary Auction

HAMMER BRAND PROVI. RI. 1945-55 UTILITY 3 /2 JACK VINTAGE AMERICAN AU – Latham's Vintage Sales

4 Colors Switchblade Spring Folding Knife Push Button Pocket Comb Oil Hairstyle Hair(Rosewood) : Beauty & Personal Care

Vintage HAMMER Brand U.S.A. Switchblade knife

Vintage American, AIK - Adams International Knifeworks