29Pcs Cobalt Drill Bit Set, 135 Degree Tip High Speed Steel with Black and Gold Finish, Stainless Steel, Plastic and Wood with Metal Indexed Storage Case 1/16"-1/2"

I bought these bits to drill into a hard steel rod that was about 1/2" in diameter. My conventional bits barely put a dent in it, and even a cobalt bit I had lying around couldn't hack it (probably since it was old and dull). I bought a ten-pack thinking I would burn up a few of them drilling the one hole, but I was pleasantly surprised that I only needed one, and it went right through the rod with no trouble at all. I did use oil to help cool and lubricate the bit, as it got very hot. I recommend these bits very highly, especially for the price.

good bits did the job i burnt up 6 bits but 1 did the job

No encontre como se abre la caja. Deben de incluir un instructivo

Junk! Burned up 5 bits trying to drill a hole using drill press and cutting oil on a 1/4 inch thick piece of flat steel.

At slow speeds with oil, no problem drilling into hard metal.

Very sharp

Great cobalt drill set. Good quality, good price.

Was missing smallest bit . But overall my husband was happy enough with the purchase.wasnt packaged well enough. The bit was the smallest and was missing