3mm Cobalt Drill Bit, M35 HSS Metal Drill Bits, for Hard Metal, Stainless Steel, 10 PCS

I make rod rockers using stainless steel and aluminum alloy material. These cut through both materials with ease and are long lasting.

Great drill bits. Cuts stainless steel with ease.

This is a great cobalt drill bit. I've needed these smaller sized bits primarily for drilling pilot holes for many of my DIY home projects. B/C of their smaller diameter, these bits lose their initial bite more quickly and can break a little more easily than larger drill bits - which is one of the main reasons to have several of these size bits on hand. I used this bit on a metal tubed bike rack - after using a center punch marking the location on the metal tube - starting and completing the drilling process was a piece of cake (see pic). I will expect these bits to last longer than their standard steel counterpart - although they too will have a finite life and have to be replaced after so many drillings. Overall, a great drill bit - my initial impression was "performed as expected" and with a supply of (10) of these bits - I'll be able to complete quite a few projects before having to purchase more. IMO, the drill bits are selling for a very fair price compared to similar products.

Will not drill "hard metal". Tried to drill out the front sight post of my Beretta to add fiber optic pipe and it won't even scratch the bluing off.

So far, these metal drill bits have been impressive. They’re sharp and have cut through metal with ease during the few times I’ve used them. The bits also feel pretty robust, holding up well under pressure. However, I can’t say for sure how long they’ll stay sharp and durable over time, but for now, they’re performing exactly as needed. If you’re looking for drill bits that work well right out of the box, these are a solid choice. Only time will tell if they maintain their edge with heavier use, but they’ve been reliable for me so far.