I dont recall the name of the kit. U-tan, or something like that.
It was a several stage process, using dry chemicals dissolved in water. Advertised as a "garment quality" tan.
Instructions said one kit would do one average deer hide.
I tried it on a fox pelt with the hair on, which isnt big at all. Hide was fleshed and dried just as the hundreds of others ive done.
Instructions were followed to the letter and the finished product took a little tan around the edges in spots but for the most part was re-soaked rawhide. (I later brained the thing and it came out fine).
I tried another kit (got one for free after I complained) on another hide, coyote this time, and I guess you could call it leather, but it was the worst quality ive ever seen, hard, stiff, and this was after using the oil provided to soften the leather. Pretty much ruined the pelt.
I talked to a gentleman with much more tanning experience than me, and he said that those dry chemical tanning formulations do in fact have a shelf life, and if they are expired they will not work. I think I paid $39.99 for my kit. Heck, you can send a deer off to the tannery and get a garment grade tan for about $60.