This is an Olsen OK pocket knife made in Seki, Japan between circa 1978-1982. In the late 1970s. This one is a factory sample prototype and still has a sticker on it from the factory. Olsen teamed up with Seizo Imai to produce models in Japan and this was one of these knives. Acquired direct from the closed factory of Seizo Imai and in storage for decades. Comes with Olsen box (may not be the correct one for this model).