What is the difference between SLEKAN Qianglekang DHEA and other brands?

It all feels the same. They all produce NMN products. The brand is also relatively small, and it is not very famous in China. Choosing NMN now depends on brand qualification. For example, do you have your own production factory and have it passed the FDA certification? What I am eating now is from Gene Harbor, and there is no problem in terms of safety, quality and qualification. I'm also a big brand, don't worry.