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#10-24 bolt size
3/8 in wrench
across-flats spanner / socket size for #10-24
#10-24 bolt — electrical boxes and small brackets.
Full specification
| System | Imperial UNC |
| Nominal diameter | 0.190 in (4.8 mm) |
| Thread pitch | 24 TPI |
| Wrench / spanner (across flats) | 3/8 in |
| Tap drill | #25 (3.8 mm) |
| Clearance hole | 13/64 in |
| Common grade / class | Grade 2 |
| Typical torque | 4 Nm (3 ft·lb) |
| Closest other-system size | ~M5 |
🔧 Torque unit converter
Pre-filled with the typical torque for #10-24 (Grade 2, dry). Edit any field to convert.
⚠️ Torque values here are general references for Grade 2 on clean, dry threads. Lubrication, coatings, and the joint material change the figure significantly. For structural, automotive, or safety-critical work, always use the torque specified by the manufacturer or engineer.
About #10-24
#10-24 is widely used in electrical boxes, panels and light brackets.
Do not confuse #10-24 (coarse) with #10-32 (fine) — the threads will not interchange.
Frequently asked questions
- What size wrench or spanner fits #10-24?
- #10-24 bolt uses a 3/8 in wrench or spanner, measured across the flats of the hex head.
- What is the torque for #10-24?
- A typical tightening torque for #10-24 bolt in Grade 2 on dry threads is about 4 Nm (3 ft·lb). Always confirm against the manufacturer spec for important joints.
- What thread pitch and tap drill does #10-24 use?
- #10-24 bolt has a thread pitch of 24 TPI and uses a #25 (3.8 mm) tap drill, with a 13/64 in clearance hole.