They worked great. I used these screw holes for my metal building. Through the R 28 caliber panel and then through the red iron. When I started I had 15 bits. 5 from the home camp and 10 from the port. Those 15 weren't enough for 40 holes. I'm on the second part of this set of 12 and have done over 300 holes. (I have to do 2500 total) I'm on the stairs most of the time so no oil or water. I use a Makita 18V drill and run it at high RPM. 30 holes. But I'm getting over 150 per hit! Keep 'em straight! and be aware that if you use metal they won't last long unless you use lube and low speed.