Pull studs (also called retention knobs) are the link between the machine drawbar and the tool holder. Pulling forces can reach 3000 daN on SA 50 spindles, making the superior material and hardening quality of EPB pull studs important. Precision machining guarantees precise positioning and safe locking of the holder in the spindle. Most machines require a standard pull stud design (DIN, ISO, BT, CAT) and some require a specific design.