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#12-24 bolt size
7/16 in wrench
across-flats spanner / socket size for #12-24
#12-24 bolt — server racks and sheet assemblies.
Full specification
| System | Imperial UNC |
| Nominal diameter | 0.216 in (5.5 mm) |
| Thread pitch | 24 TPI |
| Wrench / spanner (across flats) | 7/16 in |
| Tap drill | #16 (4.7 mm) |
| Clearance hole | 1/4 in |
| Common grade / class | Grade 2 |
| Typical torque | 6 Nm (4.4 ft·lb) |
| Closest other-system size | ~M5.5 |
🔧 Torque unit converter
Pre-filled with the typical torque for #12-24 (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 #12-24
#12-24 is the classic threading for many server-rack rails.
Server racks may use #12-24 or M6 — check before buying cage nuts.
Frequently asked questions
- What size wrench or spanner fits #12-24?
- #12-24 bolt uses a 7/16 in wrench or spanner, measured across the flats of the hex head.
- What is the torque for #12-24?
- A typical tightening torque for #12-24 bolt in Grade 2 on dry threads is about 6 Nm (4.4 ft·lb). Always confirm against the manufacturer spec for important joints.
- What thread pitch and tap drill does #12-24 use?
- #12-24 bolt has a thread pitch of 24 TPI and uses a #16 (4.7 mm) tap drill, with a 1/4 in clearance hole.