Press Button Knife Co #1000 INVINCIBLE antique Rare EBONY handled switchblade knife

Antique Press Button Knife Co #1000 INVINCIBLE Rare EBONY handled switchblade knife made in Walden, NY between 1892 and 1913 or so. The knife measures 4 7/8 inches closed and 8 9/16 inches open with iron liners and nickel silver bolsters & button. The clip blade is 94% full and mostly shiny with light scratches, spotting and some peppering and the tang is stamped PRESSBUTTON KNIFE CO WALDEN NY on the front and US PAT 470605 on the reverse. The smooth Ebony (dark wood) scales are original and pretty rare and in very nice condition. The knife works well with blade tip just above the liners closed, good snap and average lockup with about 1/8 inch up and down and a little side to side at the tip. Does rattle if shaken with blade open as most of these 100+ year old PBKC knives do. VG- condition.