Self-locking hexagon nut (locknut) with a nylon ring to prevent loosening due vibration etc. ISO 10511 supersedes DIN 985; spanner sizes 16, 18 and 21 are now designed for M10, M12 and M14 respectively. Thread diameter- M18 Pitch of thread- 1.50 mm Thread type- Metric Wrench/Spanner size- 27 mm Height- 13 mm Total height- 18.5 mm Material- Steel Surface treatment- Zinc-plated Quality- 8.8 DIN standard- 985 ISO standard- 10511 Measurements type- Metric