
| Nominal Size or Basic Screw Diameter | Head Diameter | Head Height | Head Chamfer | Hex Socket Size | Key Engagement | Wall Thickness | Edge of Head Chamfer | Length | ||
| Max | Min | Max | Min | Max | Nom | Min | Min | Max | Under Head | |
| 3/8" (0.3750) | 0.562 | 0.550 | 0.375 | 0.368 | 0.040 | 5/16 (0.312) | 0.182 | 0.143 | 0.010 | 5/8 |
| SEE NOTES 1 | 3 | 4 | 20 | 6 | 9, 10, 11 | |||||
Reprinted from ASME/ANSI B18.3 by permission of The American Society of Mechanical Engineers. All rights reserved. For a full copy of the standards, contact the ASME at http://www.asme.org/codes/.