Thus, while Torx offers tremendous advantages over traditional fasteners hex, the Torx Plus is a better option for assemblies that need a tighter grip. Advantages of Torx Plus Hex bolts and nuts have that problem, Allen bolts, which are in internal hex, have that problem. There is a fastener that doesn’t have that problem. Torx. Is that an SAE T55 Torx or is that a metric T55 Torx? Nope, it’s just a T55 Torx. The fasteners are used for both metric and SAE threads. The graduations between Torx sizes make them pretty easy to eyeball as well. Torx fasteners and drivers have been around since 1967, when the six-pointed star pattern was invented by Bernard Reiland at Camcar and patented in 1971.

Torx Plus is designed for high torque transmission. This means that higher torques can be used to securely tighten fasteners without incurring additional wear and tear on the tools. High torque capability is also very important in service situations where corrosion may increase the torque required to loosen a fastening. Tamper Resistant Torx Plus Drive

As illustrated in the figure below, the Torx design has a 15° drive angle, while the Torx Plus features a 0° drive angle. The decreased drive angle allows for less movement of the fastener relative to the head. It eliminates radial stresses at the impact points between the head and the fastener. While it’s common to use the terms Torx and star interchangeably, there’s actually a bit of a difference between the two. Much like the Allen wrench, Torx is a trademarked name and refers to a specific brand, whereas star is the generic name (much like hex keys). However, there is a difference beyond just licensing.

Slotted screw heads which accept flat-bladed screwdriver bits are very familiar. This style of screw and driver is not appropriate for automated assembly as tool alignment is not automatic. For example, if you have a screw with TX size, then you have to use a Torx Screwdriver or drive bit of TX size only. The metric system is more widely used in other countries. In the United States, the Imperial system is still used. It is based on the Roman Empire's system, which considered one foot to be the length of a human being. This means that the same tool in metric units won't fit an Imperial nut. Examples include vehicles, motorcycles, computer systems, bicycles, consumer electronics, and hard disc drives. Tamper Proof Torx What is Tamper Proof Torx?Many star bits have little improvements, such as knurled ends or ball dents to improve handle grip. While essentially the same as official Torx, these little additions tend to make third party star bits a more popular choice. Internal vs External Torx External Torx