2/Pack Solid Carbide Drill Bit for Hardened Steel Hard Ness HRa 91.3 Aerospace Standard K20 Tungsten Carbide Jobber Length Twist Drill for Metal 118 Degree Four Facet Point Fractional Size (1/4")

I rarely write reviews. However, I had to write one for these bits. They are AMAZING. Ate through my hardened steel like a hot knife through butter. Are they expensive at what is effectively $20 per bit? Yeah. Are they brittle and can break easy if you are ham-fisted with them? Oh yeah. But do they work and work WELL?? Absolutely! I can vouch that they are WELL worth the money! If you are on the fence about them because of the price, buy once cry once. These things are great! Take it slow and easy, and use a press instead of hand-held if you can (though I used them hand-held and didn't have any issues with breakage). I didn't even need to use any cutting oil, though that would be ideal. These bits spat out the finest steel chips I've ever seen. Like shiny metal shaved chocolate on a mousse! I can finally say that I know what it's like to use quality drill bits, 'cause these things rock!! MILES beyond any other bit I've ever used! Get 'em and you won't be sorry.

Don't hesitate to buy these drill bits. I broke a bolt extractor off inside of a glow plug and was in big trouble. I went to every hardware store and bought all of the best drill bits of different brands. Went home and six drill bits and a couple hours later I was only able to drill a small simple in the extractor, not much bigger than the center punch mark that I had made for a good center start. I took a break and got online and found a video on these bits, which had a link to Amazon . I bought them and within 24 hours they had been delivered. During that 24 hours I had tried a few more times to find a drill bit locally that would actually do more than just spin without actually getting anywhere into the extractor. I really didn't think these were bits from Amazon were going to do much more, but I had a little hope. I put the 1/8" drill bit in my Dewalt drill and slowly started to drill at a slow speed with little to almost no pressure and to my disbelief all of a sudden long metal shavings were falling out of the broken bolt hole........I could not believe what I was seeing! Within maybe two minutes of slow drilling, I had drilled through the one inch of broken extractor!!! I then jumped up the 3/16" bit and went right through it again. Still in shock, I can't explain how crazy awesome that was. I then had no longer had a broken off extractor to deal with and could get back to dealing with getting the broken seized bolt out. And now I'm no longer worried about ever breaking an easy out or extractor again, knowing that these bits with cut through like drilling soft wood. Both bits are in great shape and show no wear. I would recommend these to anyone that needs to drill through crazy hard metal!

I needed to drill a 5/32” hole through a piece of 1/8” very hard stainless. My first attempt was with high quality cobalt steel drill bits.. I used a drill press and oil with the slowest speed on my drill press. Effort was made to keep the bits as cool as possible but after ruining 5 identical bits with little progress it became clear that something else needed to be tried. This bit did the job easily but I did take the precaution of drilling slowly with a drill press. I stopped several times to clean away the cuttings and kept the bit oiled. I did examine the tip of the bit with 20x magnification afterwards and found two microscopic chips in the cutting edges of the blade. This should not affect the usefulness of the bit. The bits may seem to be expensive but nothing else could get the job done. I am completely satisfied with these bits.

I snapped off a torx bolt in my chainsaw, then foolishly tried to remove it with a cheap easy-out, which only made it harder. Then I tried every other drill bit I could find, in every way. Slow speed, with oil, without oil, high speed, spent hours and got almost nowhere. I made a little progress with cobalt bits, but dulled out two of them and only got halfway through. Then I tried these solid carbide bits. Nice and slow, cut right through in 20 minutes. One negative -- I did break one of the carbide bits; more my fault, got impatient and pressed down a little too hard. But these bits saved my chain saw.

Happy with the drill bits but even more so with the service from the seller. Also, the additional communication / information to ensure we're using the product correctly was greatly appreciated. Thank you!!!!

If you are looking for an item like this then you found the right one here. The quality and craftsmanship of this item is far superior to many other items like this. I have looked around for this item and have found that this one is one of the best based upon quality, craftsmanship, price and ratings. I would highly recommend going business with this Vendor.

Junk used mag press 700rpm volume didn't go 1/4 before dulling lowes Dewalt bits are equivalent

I own several full indexes of drill bits, most are high end, American made. I was trying to drill a 3/16" hole in the release plate on a S10 parking brake in my 1939 ford. Not one of my bits would even mark the surface. Ordered 2 solid carbide bits from Mars and drilled the hole with one bit. It wasn't easy but got the job done. Pricey to me at $34 for 2 but it worked.