Columbia River Knife and Tool 5510K K.I.S.S. in the Dark 2.25-Inch Serrated Blade Knife, Black

A thumb stud is used to one-hand open the blade, and as the blade is fully rotated open, the frame lock snaps crisply in behind the blade to give a sound lockup. The blade can be closed with one hand, simply by releasing the frame lock. The Original K.I.S.S. blade shape is Tanto-inspired Chisel-Point grind on the front and flat on the backside so that when the blade is closed onto its handle/frame, the precision fit effectively "seals" the cutting edge to the frame, even though it's exposed.