Difference Between :Torx, Torx Plus, 5 Star Socket & Bits
Torx History and Applications
TORX was developed by Camcar Textron in the late 1960s as a six-lobe drive system designed for improved torque transfer and reduced cam-out. Today, TORX, TORX PLUS, and 5-point star are commonly used as drive profile types for sockets and bit sockets. These terms describe the profile shape only, not the screw thread size or the ratchet square drive size, such as 1/4", 3/8", or 1/2".
Common applications include electronics, automotive and motorcycle parts, bicycle brake rotors, and tamper-resistant equipment.
Compare Torx sizes below to choose suitable PROJEN tools. Always confirm the equipment's fastener profile and specifications.
Illustrative applications; fastener types vary by equipment. Confirm the manufacturer's specifications.
1. TORX vs TORX PLUS vs Pentalobe
The difference is more than the number of points (5 or 6 points) . Each profile changes how the tool grips the screw.
TORX — a common repair profile. Six rounded lobes transfer torque efficiently while reducing the tool's tendency to slip out.
TORX PLUS — broader contact. Its six wider lobes spread driving force, reducing contact stress and helping limit tool wear.
Pentalobe (5 Star) — a specialized precision fit. Five rounded lobes require a matching driver, often for selected Apple enclosure screws.
Which profile suits your task?
| Quick question | TORX | TORX PLUS | Pentalobe / 5-point star |
| What looks different? | 6 rounded lobes | 6 wider, fuller lobes | 5 rounded lobes |
| What is the key feature? | Efficient grip with reduced cam-out | Broader contact reduces stress and wear | Specialized five-lobe fit for small device screws |
| Where might I use it? | Cars, bicycles and electronics | Automotive and industrial assembly | Selected Apple device enclosures |
| Which tool should I choose? | Correct T size | Correct IP size | Device-specified Pentalobe size |
Choose the profile specified by the equipment, then confirm the size. A similar-looking tool is not enough.
Two differences worth checking
Six points do not mean identical fit. T20 and IP20 belong to different drive families. Prefer the specified driver.
2. How to identify the Socket Bit Profile (Sample: Torx Bit & E socket)
Internal T (Torx T10, T12 etc): A six-lobe recess takes a male bit.
External E (E16, E20 etc) : A raised six-lobe head takes a female socket.
Security T(Tamperproof Torx TT10, TT12 etc): A center post requires a matching center-hole bit.
Ordinary six-lobe Torx is not automatically tamper-resistant.
Do not assume lookalike profiles are interchangeable.
3. Read the Right Measurement
(O) Measure across opposite points of the working tip when checking internal Torx sizes.
(X) Thread diameter is a separate measurement.
(X) A 1/4-, 3/8- or 1/2-inch square drive describes the ratchet connection, not the fastener size.
4. T Size Chart and E Size Chart
Internal T: approximate tool-tip width
| Size | mm | Size | mm |
| T1 | 0.81 | T10 | 2.74 |
| T2 | 0.93 | T15 | 3.27 |
| T3 | 1.10 | T20 | 3.86 |
| T4 | 1.28 | T25 | 4.43 |
| T5 | 1.42 | T27 | 4.99 |
| T6 | 1.70 | T30 | 5.52 |
| T7 | 1.99 | T40 | 6.65 |
| T8 | 2.31 | T45 | 7.82 |
| T9 | 2.50 | T50 | 8.83 |
Values follow Wiha’s metric point-to-point table. These Torx sizes are approximate identification references.
This T1–T50 reference does not cover every available size.
External E: identification and selection
External Torx sizes use E designations. A raised six-lobe fastener head requires a matching female E-Torx socket.
E10 is a size designation, not a 10 mm measurement. T and E tools are not interchangeable.
According to Camcar, external TORX sockets allow smaller diameters than standard hex sockets for the same fastener size.
For service work, follow the equipment's specified E size, confirm full seating, and check clearance.
The ratchet's square drive and the required tightening torque are separate specifications.
External Torx: standard drive-size selection
These are fastener-size selection references, not socket opening measurements or ratchet square-drive sizes.
| E socket size | Inch fastener size | Metric fastener size |
| E4 | #6 | M3 |
| E5 | #8 | M4 |
| E6 | #10 | M5 |
| E8 | 1/4" | M6 & M7 |
| E10 | 5/16" | M8 |
| E12 | 3/8" | M10 & M11 |
| E14 | 7/16" | M12 |
| E16 | 1/2" | |
| E18 | 9/16" | M14 |
| E20 | 5/8" | M16 |
| E24 | 3/4" | M18 & M20 |
| E28 | 7/8" | M22 |
| E32 | 1" | M24 & M27 |
| E36 | 1-1/8" | M30 |
| E40 | 1-1/4" | M33 |
| E44 | 1-3/8" | M36 |
E16's metric entry is blank in the source; no metric value has been inferred.
Source: Camcar TORX drive-system flyer, page 2.
Actual fastener designs vary. Confirm the equipment manufacturer's specified E size and socket fit before applying torque.
The T chart aids identification; the E guide explains selection. Neither supplies tightening specifications or a T-to-E conversion.
4. PROJEN Tool Recommendations
Each panel pairs an actual product-detail photo with an AI-generated category-use illustration, not a product photograph or fitment guarantee.
CA000733 9pc Socket Torx Bit Set
Features: Nine CR-V bit sockets with 3/8-inch drive, organized on a rail.
Use case: Internal Torx fastening during mechanical or automotive maintenance, with suitable straight access.
Torx sizes: T10, T15, T20, T25, T30, T40, T45, T50 and T55.
Check: T27 is absent. Verify individual sizes before ordering.
Left: actual product detail. Right: AI illustration. Internal Torx engagement.
CA000732 10pc Impact Torx Socket Set
Features: Ten CR-V female E sockets with 1/4-inch and 3/8-inch drive connections.
Use case: Gripping raised external Torx heads during automotive fastening and removal.
External Torx sizes: E4, E5, E6, E7 and E8 use 1/4-inch drive.
E10, E12, E14, E16 and E18 use 3/8-inch drive.
Check: E11, E20 and E24 are absent.
Left: actual product detail. Right: AI illustration. External Torx profile matching before engagement.
CA000925 11pc Tamper Torx Set
Features: Eleven CR-V center-hole bits accommodate matching security pins.
Use case: Servicing matching six-lobe security fasteners on sensors, electronics or anti-theft hardware.
Torx sizes: T10, T15, T20, T25, T27 and T30 use 1/4-inch drive.
T40, T45, T50, T55 and T60 use 3/8-inch drive.
Check: This is not a five-lobe security set; confirm the equipment’s exact fastener.
Left: AI-restored product illustration with reconstructed tip details. Right: AI-generated use illustration. Images are illustrative, not dimensional references.
CA263900 6pc Torx Screwdriver Set
Features: Six screwdrivers combine a 250 mm shaft and 100 mm handle for 350 mm total length.
Use case: Reaching recessed Torx screws through a clear, straight access path.
Torx sizes: T10, T15, T20, T25, T27 and T30.
Check: Shaft diameter is 5 mm for T10–T25 and 6 mm for T27–T30. Confirm clearance.
Left: actual product detail. Right: AI illustration. Long-shaft access to recessed fasteners.
CA002115 5pc Universal Joint Star Bit Set
Features: A 3/8-inch CR-V universal-joint socket holds four interchangeable S2 bits.
Use case: Approaching obstructed fasteners where surrounding components limit straight ratchet access.
Torx sizes: T30, T40, T45 and T50.
Check: Keep the bit aligned with the fastener while the joint changes the drive approach.
Left: actual product detail. Right: AI illustration. Joint changes approach while the bit remains aligned.
6. Check Fit Before Applying Torque
- Identify: check service information, lobe count and any center post.
- Clean: remove debris blocking engagement.
- Seat: insert the specified tool fully by hand, without forcing.
- Inspect: excessive movement or incomplete seating calls for checking size, profile, wear and obstruction.
- Operate: maintain alignment and follow the equipment manufacturer's torque procedure.
A worn fastener may need a dedicated extraction method.
Use impact equipment only with tools rated for that use; color alone is not proof.
7. FAQs
Does T25 mean 25 mm? No; its approximate tip width here is 4.43 mm.
Can a hex key replace Torx? Use the specified profile; a poor match can damage the fastener.
Can I use a generic Torx torque chart? Tool capacity is not the joint's tightening torque. Follow the equipment specification.
8. Conclusion
Specify Torx sizes, profile, drive connection, reach and operating method before ordering.
For B2B assortments and private-label packaging, contact PROJEN with your requirements.
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Profile reference: Acument TORX PLUS guidance.
History: Camcar. Design: Acument TORX guidance.
