|
Major
Thread & Head Diameter (Gage) |
|
Types of Screw |
|
Heads |
|
Flat Head |
| Flat top
surface with a countersunk bearing surface. |
|
Pan
Head |
| Flat bearing
surface, a semi-elliptical top surface, and cylindrical side
surface. |
|
Truss Head |
| Low profile
semi-elliptical top surface with flat bearing surface. |
|
Oval Head |
| Slightly
rounded top surface with a countersunk bearing surface. |
|
Hex
Washer Head |
|
Round Washer Head |
| Built-in washer
provides a larger bearing surface. |
|
