Hex Head vs. Pan Head
Comparing 2 standards across 13 specifications. 13 key differences identified.
Hex Head Bolts (standardized under ISO 4014 / DIN 931 for partially threaded bolts and ISO 4017 / DIN 933 for fully threaded tap bolts) feature a 6-sided external polygon head driven by open-end wrenches, box wrenches, or ratcheting sockets. It is the global benchmark for high-torque heavy structural and automotive clamping.
Pan Head screws (standardized under ISO 7045 and DIN 7985) feature a low-profile rounded top, vertical cylindrical outer sidewalls, and a flat horizontal bottom bearing surface. Providing clean aesthetics and strong clamping force without cutting into workpiece materials, it is the most common machine screw head in electronics and appliance assembly.
Specification Comparison Table
13 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard Specifications
|
ISO 4014 (Partial thread) / ISO 4017 (Full thread) / DIN 931 / ASME B18.2.1 | ISO 7045 / DIN 7985 / ASME B18.6.3 |
|
Head Geometry
|
6-sided external hexagon with flat top face and circular washer face underside | — |
|
Common Metric Wrench Sizes
|
M6 (10mm), M8 (13mm), M10 (16/17mm), M12 (18/19mm), M16 (24mm) | — |
|
Common Imperial Wrench Sizes
|
1/4" (7/16"), 3/8" (9/16"), 1/2" (3/4"), 3/4" (1-1/8") | — |
|
Strength Markings (Metric)
|
Class 8.8, 10.9, 12.9 stamped directly on head top | — |
|
Strength Markings (Imperial)
|
Grade 2 (plain), Grade 5 (3 radial lines), Grade 8 (6 radial lines) | — |
|
Flanged Variant
|
DIN 6921 (Hex head with integrated wide washer flange) | — |
|
Head Top Geometry
|
— | Slightly domed / curved low-profile top surface |
|
Outer Edge Geometry
|
— | Vertical cylindrical sidewalls with smooth radiused top transition |
|
Bearing Surface Profile
|
— | 100% Flat horizontal bearing surface |
|
Recess Recesses Supported
|
— | Phillips (PH), Pozidriv (PZ), Torx (TX), Slotted |
|
Countersinking Required
|
— | No (Mounts completely proud of the workpiece surface) |
|
Primary Applications
|
— | Consumer electronics, sheet metal electrical enclosures, general machinery |