This is something very uncommon to find, a large ubu wakizashi from the Nambokucho period. Bizen Sadamitsu was a smith who worked in mid Nambokucho (circa Enbun, 1356) as part of the Kozori Bizen school. It has the large dimensions and wide mihaba one associates with that time period. Nagasa: 37.8cm, moto-haba: 32cm, kasane: 7mm. The hamon is a very active choji-ba with utsuri. The jihada is itame, but is coarse in areas and there are kitae-ware, which are pictured. The nakago is ubu. This piece has NTHK papers which place the blade specifically with Kozori Sadamitsu in Enbun. There is a one piece copper habaki and a high quality shirasaya with tsunoguchi.