This class consists of TOKIWASAN and TAIHOZAN MARUs, both completed in 1938 for Mitsui Bussan K.K. TOKIWASAN MARU was requisitioned by the IJA in ’38 and served until Jul ’44 as Army transport No. 395. From then, she went under IJN control as a general requisitioned transport (B-AK) until being torpedoed and sunk by an American submarine in Sep ’44. TAIHOZAN MARU also was requisitioned by the IJA in ’38 and served as Army transport No. 515 until Apr ’41 where she was requisitioned by the IJN and registered in Oct ’41 as an auxiliary water tanker. She also was torpedoed and sunk by an American submarine in Mar ’43.