I don't know about Arm & Hammer, but some companies don't produce and sell the entire phage but only a specific phage enzyme, that the phage uses to lyse (rupte

I don't know about Arm & Hammer, but some companies don't produce and sell the entire phage but only a specific phage enzyme, that the phage uses to lyse (ruptering of the cell wall) the bacteria (they are called endolysins). They are much easier to mass produce than phages.