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M27 bolt size
41 mm wrench
across-flats spanner / socket size for M27
M27 bolt — large structural and industrial plant.
Full specification
| System | Metric coarse |
| Nominal diameter | 27 mm |
| Thread pitch | 3.0 mm |
| Wrench / spanner (across flats) | 41 mm |
| Tap drill | 24.0 mm |
| Clearance hole | 30 mm |
| Common grade / class | 8.8 |
| Typical torque | 1050 Nm (774 ft·lb) |
| Closest other-system size | ~1 inch |
🔧 Torque unit converter
Pre-filled with the typical torque for M27 (8.8, dry). Edit any field to convert.
⚠️ Torque values here are general references for 8.8 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 M27
M27 is used in large industrial structures and heavy plant anchoring.
Specialised sockets are needed — a 41 mm is outside many common socket sets.
Frequently asked questions
- What size wrench or spanner fits M27?
- M27 bolt uses a 41 mm wrench or spanner, measured across the flats of the hex head.
- What is the torque for M27?
- A typical tightening torque for M27 bolt in 8.8 on dry threads is about 1050 Nm (774 ft·lb). Always confirm against the manufacturer spec for important joints.
- What thread pitch and tap drill does M27 use?
- M27 bolt has a thread pitch of 3.0 mm and uses a 24.0 mm tap drill, with a 30 mm clearance hole.