Today there is a purchase, and the person who wants to buy it is R142b, that is, 1-chloro-1,1-difluoroethane. It is the core of the purchase. The direction to follow is "Buy R142b 1 chloro 1 1 difluoroethane". I would like to obtain this item to meet my needs, hoping to get what I want, and find a suitable way to buy it.