
Learn the dimension of M8 Countersunk Head Allen Screws, including screw length, thread pitch, and head size. Find the right screw for your project here.
DIN 7991 - The German Industrial Norm for metric screw threads with coarse pitch. Learn about dimensions, tolerances, materials, and applications. Find DIN 7991 screws and bolts for your next project.
Specification #
| Standard | DIN 7991 |
| Name | Hexagon socket countersunk head cap screws |
| Material | Alloy Steel / High Tensile |
| Thread | Metric thread |
| Head shape | Countersunk head |
| Drive Type | Hexagon socket |
| Grade | 10.9 |
| Surface Finish | Black Oxide |
| Color | Black |
| Measurement System | Metric |
| Pitch Type | Coarse Pitch |
Dimension #

| Size | Dia | Thread Dia | Head Dia (mm) | Head Height (mm) | Allen Key Size | Thread Length |
|---|---|---|---|---|---|---|
| M3 | 3mm | 2.86mm | 5.7 – 6 | 0.95 – 1.2 | 2 | 30mm |
| M4 | 4mm | 3.82mm | 7.64 – 8 | 1.5 – 1.8 | 2.5 | 40mm |
| M5 | 5mm | 4.82mm | 9.64 – 10 | 2.05 – 2.5 | 3 | 40mm |
| M6 | 6mm | 5.7mm | 11.57 – 12 | 2.25 – 2.5 | 4 | 40mm |
| M8 | 8mm | 7.64 | 15.57 – 16 | 3.2 – 3.5 | 5 | 40mm |
Note: The values provided are based on standard specification, the details are for information purpose only. To verify the dimension accuracy customers are requested to buy sample and verify before making bulk purchases. Always feel free to reach us for any help.









