The three generations are Digital China, Zhongke Hope and Shang Qi Science and Technology.
The seven nuclear generations are Shanghai Nanyang, Shanghai Zhendong, Shanghai Dongji Digital, Shanghai Soft Sound Technology, Jingcheng Hengyi, Yingshite and Hangzhou Wolian.
There are countless other dealers. Suzhou Nanyang you selected is a subsidiary of Shanghai Nanyang. The goods are very good, no problem.