This instrument is imported from Japan, and its effect is similar to that of ancient warm moxibustion. The part of joint pain must be poor blood circulation, and this instrument can promote blood circulation in this part and improve the basal body temperature of all parts of the human body.
A shop named "Youyou Yangshengtang" on Taobao sells it at a price of around 7,000 yuan.
There are also some imported medicines to relieve rheumatic joint pain: plaster and medicinal oil (Tuokuhai, Nanyang Li Qian Zhuifeng Oil, Long Jun Qufeng Oil, etc. ), these are also very good.
I wish you a speedy recovery!