Phosphated steel
| d | 3.5 | 3.8 | 4.2 | 4.8 |
| dk | 8.5 | 8.5 | 8.5 | 9.1 |
| L | ||||
| 19 | + | |||
| 25 | + | |||
| 32 | + | |||
| 41 | + | |||
| 45 | + | |||
| 51 | + | |||
| 55 | + | |||
| 65 | + | |||
| 75 | + | |||
| 90 | + | |||
| 100 | + | |||
| 110 | + | |||
| 120 | + | |||
| 140 | + | |||
Drywall screws have become a standard fastener for attaching drywall sheets to metal frame structures.
A drywall screw for metal has a countersunk head with a cross slot and a fine thread pitch, unlike a drywall screw for wood, which has a wide thread pitch.
This type of fastener is also called a black screw, as it is made of steel with a phosphated coating.
Marking
d – thread diameter
d k – diameter of the countersunk head
L – length of the screw