Hammer Brand Imperial Serpentine Jack Black jigged vintage switchblade knife

Vintage Hammer Brand Serpentine Utility Jack Black jigged switchblade knife from the 1950s made by the Imperial Knife Co of Providence, RI and was designated the model JM98PB. The knife measures 3.5 inches closed and 6.25 inches open with steel liners and nickel silver plated button & safety. The clip blade is 99% full or better with original finish under patina with some spotting and light scratches and the tang is stamped HAMMER BRAND USA with a picture of an arm holding a hammer and the back is marked P 2170537 2281782. The handles (scales) are hollow punched steel with black wrap in great condition with minor shrinkage. The knife works GREAT with the blade tip seating deep when closed, strong snap and very good lockup with less than 1/16" movement at the tip. Barely rattles if shaken with the blade open. Safety works. VG+ condition.