I ordered from Amazon. Here are details.
COMFIER Back Massager Seat Cushion w/heat, 10 vibration motors. $53.99.

I turn on power, select upper back, lower back, seat and select high intensity. I do 30-minutes in chair while watching TV!

Google Osteogenic Loading.
My T-scores range from -2.1 to -2.8 in the various regions.

All the best as we navigate this osteoporosis journey.