Tuff Nut T-Nuts for Taig Mill (Bag of 8) Steel T-nut for Taig. Black Oxide finish. Lifetime warranty. Tuff Nuts are custom engineered to be the last t-nuts you will ever buy. If you break one, return it to us with an explaination of what happen and we will replace it with 2 nuts. No more messing around with square nuts trying to get them to tighten. Custom designed specifically for the Taig Mill