A ballpoint allen key (or hex key) has a rounded, ball-shaped tip on the long arm, allowing it to drive socket-head screws at an angle (up to about 25 degrees) for better access in tight or hard-to-reach spots where a straight-on angle isn't possible. These tools combine the standard hexagonal end for high torque with the angled ball end for flexibility, making them ideal for furniture assembly, bike repair, and other jobs needing extra reach.