Huh! I've never seen it before. I don't know the ingredient list from your pic, but I well imagine it's just a high-protein feed of sorts. When my girls went through their first (juvenile) molt I just gave them hard-boiled eggs, shell and all, crushed real fine, every other day...gives them a boost to produce their new feathers. I'll be interested to see what others have to say!
There are other discussions you can search. Some folks report no difference and some gave it high ratings.
Haven't tried it during molt, but bought it last year when my chickens got bare butts from a feather picker. Didn't make a difference, but they were not molting & didn't realize at that time the feathers would not come back til molting.
It seems to be a safe product, but I think the only real difference between this and layer feed is a higher protein content. My girls didn't like it as well as their regular feed, so switched back before using one bag.
Mine are now having their first real molt and with protein supplemented treats - mealy worms, eggs, some meats, they are getting new feathers and still laying eggs.
IMO supplementing protein in diet during molt and continuing their regular feed is the way to go. But for me, I had to mail order and didn't think it worth the extra cost.
Since you already have it, I would go ahead and use it if your flock will eat it.