Kigawa was called Optochrome up to around 1940 (McKeown), and was responsible for the better-known Tubasa cameras, in various formats (including a Tubasaflex and a Rectaflex 120 TLRs, both fairly similar to this Graceflex - the frontal treatment is the only noticeable variation, from the pictures in Sugiyama). A simple but functional design made from assembled metal pressings rather than castings.
Taking lens is Bessel 80mm f3.5
Shutter unnamed "K.K.K. 1/10 to 1/200