Press Button Knife Co Medium double bone switchblade knife model 100 w file blade

Antique Press Button Knife Co medium double with jigged bone scales (handles) model 100 with file blade made in Walden, NY sometime between 1892 and 1923. It measures 3 3/8" closed and 6 11/16 inches with both blades open and has brass liners and nickel silver buttons. It is the middle of three sizes of switchblade doubles made by the company. The blades are both 94% full or better with light patina, light scratches and some spotting. Both blades are marked PRESS BUTTON KNIFE CO WALDEN NY and both are stamped US PAT 470605 on the backside so likely made before 1913. The picked bone scales are attractive and in excellent condition with no cracks. The knife works well with both blade tips below the liners closed, good snap and excellent lockup with both blades tight which is unusual. Slight kickback on small blade, but locks when pushed into the full open position. VG condition.