The stone lock itself is worthless, and the price is clearly marked on Taobao, but the stone lock technology is much more difficult and comprehensive than dumbbells and kettle bells. Stone lock is one of the main formats of "bow and arrow sabre" in China 1000 martial arts examination, not a wild way (it is useless to take this punch when you get the first place in the martial arts examination, so you should take bow and arrow sabre),,, you can refer to the first monograph of China Stone Lock Kung Fu, "China Stone Lock Kung Fu Primary Training". It has been successively collected by the best martial arts museum in China, the best sports university in China, the best universities in Chinese mainland (Peking University, Tsinghua, Fudan University, Zhejiang University, Jiaotong University and Tongji University ranked ninth in QS2020), the best universities in China, Hong Kong, Macao and Taiwan (HKU, AOU and NTU ranked first in their respective regions in QS2020) and the best national library in the world (Britain and China). You can borrow it.