PRESS BUTTON KNIFE CO "M" Invincible antique automatic knife w Custom blade

PRESS BUTTON KNIFE CO "M" Invincible antique automatic knife w Custom blade. The knife was made in Walden, NY sometime between 1892 and 1923 and was designated the model 1000. This knife has a Custom replacement blade that is very nice and marked simply with the letter M. Not sure who made the blade, but they did a Great job! The knife measures 4 7/8 inches closed and 8 9/16 inches open with brass liners and nickel silver bolsters, button & pins. The clip blade is 100% full with original mirror finish and the tang is marked M. The picked bone scales are in very nice condition and indicate that the knife was likely made before 1910. The knife works great with blade tip deep in the well closed, good snap and TIGHT lockup! Very nice antique knife with a modern custom blade. EX condition.