What kind of activated carbon is good?

Shenyang Jiahuan activated carbon is good. After my home was renovated, I heard from a friend that Jia Huan's activated carbon was good. My friend used Jia Huan to purify water in Shanghai, and the effect was good. After the renovation, in addition to formaldehyde missed it, and a friend recommended buying his house, which was really good. After a week or so, the smell in the room was much better.