Okada 16mm cameras
The Okada company was commonly referred to as "Okako", causing some confusion -- at least outside of Japan. They made a few early, post-War cameras, most of which are hard to find. They also made 17.5mm and 8mm cameras.
(1950) A pistol camera for 10x14mm negatives in Mamiya 16mm cassettes. The 35mm f4.5-11 lens is fixed-focus. Shutter speeds of 1/25-1/100. Pop-up viewfinder. Pulling the trigger took the shot, advanced the film, and cocked the shutter.
(1950) 22mm (f3.5) fixed-focus lens with speeds of B, 1/25-1/200. Image size of 11x15mm in special cassettes. Viewfinder on top of the camera. Okada also produced a Camera "A" No. 1 but that camera used 8mm film although it was similar in appearance.