Press Button Knife Co #1000 INVINCIBLE antique switchblade knife

Vintage Press Button Knife Co INVINCIBLE model switchblade made in Walden, NY sometime between 1912 and 1923. The knife measures 4 7/8 inches closed and 8 1/2 inches open with steel liners and nickel silver bolsters & button. The clip blade is about 1/4 inch short and 92% full, or better with some light scratches and the tang is stamped PRESS BUTTON KNIFE CO WALDEN, NY and the backside is blank. The jigged bone scales are in very good condition with no cracks. The knife functions well with the blade tip well below the liners closed, opens strong when button pressed and locks open with about 1/8" up and down and little side to side. It does rattle if shaken with the blade open as most of these do. This is a nice working example of a 100+ year old American made switchblade. VG+ condition.