I used this shank to adapt a Wen drill press to use core bits. I made 16 holes in one inch thick sheet steel and various other items. The shaft is precisely milled and works great. It's not self-cooling, but I've cooled my bits with a penetrating oil spray and it's been fine. I can pull it out when I'm done and use the Jacobs cartridge anytime. One suggestion, they stay in place through friction and need to be kept clean. It is recommended to put it in a bag or plastic box when not in use to protect it from dust or corrosion.