5/64''inch HSS M35 Cobalt Twist Drill Bits,High Speed Steel,Pack of 10,Suitable for Steels,Cast Iron,Copper and Other Metals（5/64inch）

These are cheap bits and not sharp enough to cut through the steel stock I’m working with. I’ve used other bits with much better luck. I use 3.5mm much more than other sizes so I decided to give these a shot since the price was reasonable. They hardly even make a dent in the steel. It was worth a shot, but it was one of those attempts to save money that ultimately cost more in the long run.

Have a busted bolt in a small motor cycle valve body, The bits didn't cut into busted bolt. Tried them all. But didn't break either

I use these to drill hard disks prior to recycling. Sometimes I get in older drive cases made from heavy duty aluminum alloy, not the cheaper aluminum most drives are made of today. The bits still work great, just a bit slower drilling. Highly recommend.

I have been working on a project and had to drill holes in metal that turned out to be a little harder than expected. It dulled my Snapon bits on the first hole. Finished the holes with the first bit. Expensive but worth it. Good product!!!

These drills last longer than tungsten bits.

Happy costumer

Great drill bits for hard metal

All good, thanks.