Hex Head vs. Wafer Head
Comparing 2 standards across 12 specifications. 12 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.
Wafer Head screws (Modified Truss / K-Lath / Framing Screws) feature an ultra-flat, razor-thin head with an integrated wide circular clamping rim and a flat underside. Engineered with a self-drilling TEK point or sharp piercing tip, they are standard in light-gauge steel stud framing, metal lath attachment, and drywall partition construction.
Specification Comparison Table
12 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard Specifications
|
ISO 4014 (Partial thread) / ISO 4017 (Full thread) / DIN 931 / ASME B18.2.1 | ASTM C1002 (Steel studs) / ASTM C954 / DIN 7504-M |
|
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 Thickness
|
— | Ultra-thin low profile (~1.0 mm to 1.5 mm thick) |
|
Head Outer Diameter
|
— | Wide circular flange (10.0 mm to 11.5 mm on #8 screws) |
|
Point Types
|
— | Self-Drilling TEK Point (#2/#3 drill point) or Sharp Piercing Point (Type S) |
|
Common Drive Recess
|
— | Phillips #2 / Square #2 |
|
Primary Applications
|
— | Steel stud framing, stucco metal lath, HVAC ductwork, M.2 SSD hold-down screws |