What feature do torque screws have on their heads?

Torque screws are specifically designed with a square indentation on their heads to accommodate a torque wrench or a specific type of driver that can apply precise amounts of torque. This design helps ensure that when tightening or loosening the screw, the pressure applied is controlled, allowing for consistent and accurate fastening. The square shape of the indentation provides a secure grip for the tool, which is essential for applications that require a certain level of tightness to maintain structural integrity and prevent over-tightening or damage to the materials being fastened.

In contrast, other head shapes, such as rounded indentations, threading, or hexagonal shapes, serve different purposes in fastening technology but do not provide the same level of torque application control that a square indentation does.