SUPER AUTOMATIC 23cm Vintage DA OTF Metal frame Japanese switchblade

Vintage Japanese SUPER AUTOMATIC Metal frame DA OTF switchblade knife. I believe these are from the 1960s or 70s, but not sure. It measures 22.5cm (8.75 inches) open and is quite heavy. The blade is stamped STAINLESS STEEL JAPAN and appears to be nearly full with original finish and is slightly tipped (tiny bit of the tip missing). The frame is silver and shiny and non-magnetic and too heavy to be aluminum. Black inserts on both sides of the knife and the front one says SUPER AUTOMATIC in raised letters. The knife works great. Blade opens when knob pushed forward and closes when it's pulled backwards. Sometimes these misfire and you just need to pull the blade fully open to reset it. Neat collectible vintage Japanese OTF.