Did what I needed them to after I sharpened them. Out of the box, I couldn't get them to bit, but after using an old Drill Doctor, these tore right through the stuck bolt in my car's engine block (which, as you might know or at least can guess, is not a fun place to be extracting a broken bolt from). Minus one star because they weren't sharp enough to do the job out of the box, but still four stars for being good steel and getting the job done.

Best quality product out there

This is a must have, even if your not an avid mechanic. Home use is valid reason for these. If you've ever sheared off the head of a bolt, you immediately wish you had these. Sometimes, the bit will grab the sheared off bolt or screw and just back out! Win Win Win add to cart.

Only used once. Works as expected.

Quality company products. Great price points.

Perfect. Couldn't be happier with this purchase. They last a good while. They're strong enough to get bolts unstuck. Highly recommend.

I used these to drill out a grade 5 bolt, they worked well.

Very high quality, driller in metal like a butter

Very strong, sharp and durable. I was hoping they would extract rusted studs in an engine, I was hoping for too much, studs were rusted to the head, they drilled all the way through the studs without dulling.