A classic revisited, a tribute to a war veteran: MK2.1 is the restyling of the MARK 2 fighting dagger, one of the most widespread knives in World War II. Our aim with such an ambitious design project was to retain the characteristic qualities of the original, while only introducing those changes we deemed strictly functional to its improved effectiveness. The blade is cobalt steel, with AISI 303 and AISI 304 employed for other parts, and glass-fiber-strengthened nylon replaced leather on the grip. It retains the ergonomics of the original Mark 2 while all structural parts have been oversized to obtain a sturdy and high-performance multipurpose knife. The most significant changes are aimed at fixing the known “weak spots” of the parent knife: these include toolless in-the-field disassembly ability, a straightened modified Bowie profile making for easier edge maintenance, and barrel-shaped grooves on the hilt which both help user properly orient the blade in the dark and improve user’s grip in twisting movements (“screwdriver” effect). Minor additions include safety-cord holes in the tang and pole-mounting holes on the front guard. Our usual Extrema Ratio “side groove” replaced the traditional blood-groove fuller for improved looks and reduced weight. Includes a standard thigh sheath with automatic retention mechanism and protective flap.