We have developed a device for the prosthetic leg using SoftMRF® in collaboration with Hashimoto Gishi Seisaku K.K. and has now been put to practical use for the first time in the welfare field. It passed various tests, including an endurance test, and was presented as a new lower limb orthotic foot joint (MR-AFO) at the Annual Meeting of the Japanese Association of Rehabilitation Medicine held on June 9-11, 2016.