T8 Torx Screwdriver: Size, T8H & Uses

The T8 Torx is one of the most commonly needed small Torx sizes. With a 2.31 mm point-to-point measurement, it sits at the boundary between precision electronics and light mechanical applications. If you have ever tried to open an Xbox controller, swap a Ring doorbell battery, or disassemble a hard drive, you have needed a T8.

T8 Torx Specifications

Specification	Value
Torx Size Designation	T8
Point-to-Point (mm)	2.31
Point-to-Point (inch)	0.091"
Security Variant	T8H (center hole for security pin)
External Torx Equivalent	E-4 (uncommon at this size)

T8 vs T8H (Security Torx)

Many devices that use T8 screws actually use T8 security (T8H) variants. The security screw has a small pin protruding from the centre of the star recess. A standard T8 bit will not fit - it bottoms out on the pin. A T8H security bit has a corresponding hole in its centre to clear the pin. If your T8 bit will not seat into a T8 screw, check for a security pin.

Common T8 Applications

Device/Application	T8 or T8H?	Notes
Xbox One/Series X controllers	T8H (security)	All case screws use T8 security
Xbox One/Series X console	T8H / T10H	Mix of T8H and T10H security screws
Ring Video Doorbell	T8	Battery compartment and mounting screws
Hard drives (3.5" desktop)	T8	Case screws on many Seagate and WD models
Some Samsung TVs	T8	Back panel screws
Arlo security cameras	T8	Mounting and case screws
Some motorcycle components	T8	Small fairings, mirrors on select models

Buying a T8 Screwdriver

T8 bits come in precision screwdriver sets, individual screwdriver handles, and bit kits. For consumer electronics, a T8H security bit is the safer buy - it works on both standard T8 and security T8H screws. A standard T8 bit only works on non-security screws.

Pro Tip

Always buy T8H (security) instead of plain T8. The T8H bit fits both security and standard T8 screws. A plain T8 only fits non-security screws. There is no reason not to get the security version.

Frequently Asked Questions

What size is a T8 Torx in mm?

T8 Torx measures 2.31 mm point-to-point across the star pattern. This is the distance between two opposite points of the six-pointed star.

What is the difference between T8 and T8H?

T8H is the security (tamper-resistant) version of T8. The screw has a small pin in the centre of the star recess. A T8H bit has a hole to accommodate this pin. A standard T8 bit cannot fit into a T8H screw because the pin blocks it.

What screwdriver do I need for an Xbox controller?

Xbox One and Xbox Series X/S controllers use T8H (T8 security Torx) screws. You need a T8 security Torx screwdriver or bit - a standard T8 will not fit due to the centre security pin.

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