I use these in my [ASIN:B003DQO7ES Bosch RH328VC 1-1/8" SDS rotary hammer]] for concrete drilling. Their durability is about the same as Bosch's SDS drills (to be honest I can't tell if they drill longer or shorter so let's call them equal in durability) but about half the price. I was very happy with them and bought a few more Hawera brand tips after trying this particular one. I highly recommend them. The only reason it's four stars instead of five is because you can always use more durability. It would be nice if they were somehow magically cheaper than Bosch drills and lasted longer.