This isn’t equipment just a recommendation. Keep doing your exercises at home even after you complete PT. I had both knees replaced 3 years ago and was religious about doing my PT exercises at home and even did them for awhile after I “graduated.” Last week I had physical therapy for my back and the therapist was wondering why I was bent at the knees. I thought I was standing straight up. He had me sit on the bed and with my legs extended straight out where it should at 0 degree extension mine was at 20 degrees. I don’t know if I never got to zero degrees 3 years ago and they were negligent in telling me or if it happened over time. Either way it would have been prevented by continuing the exercises.