Button Head vs. Wafer Head
Comparing 2 standards across 11 specifications. 11 key differences identified.
Button Head Cap Screws (BHCS, standardized under ISO 7380) feature a low-profile rounded dome with a wide load-bearing base and an internal hex or Torx drive recess. Designed for applications requiring a smooth, snag-free finish and low vertical clearance, they provide clean aesthetics on exposed consumer products, 3D printers, and automotive interiors.
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
11 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standard Specifications
|
ISO 7380-1 / ASME B18.3 | ASTM C1002 (Steel studs) / ASTM C954 / DIN 7504-M |
|
Primary Applications
|
3D printer motion carriages, motorcycle fairings, electronics rack enclosures | Steel stud framing, stucco metal lath, HVAC ductwork, M.2 SSD hold-down screws |
|
Head Profile
|
Low-profile smooth domed contour | — |
|
Bearing Base Diameter
|
Extra-wide circular bearing base (approx. 1.75 × shank diameter) | — |
|
Drive Recess
|
Internal Hexagon (Allen) or Hexalobular (Torx / ISO 7380-2) | — |
|
Torque Rating
|
Reduced torque rating compared to DIN 912 socket caps (due to shallower socket depth) | — |
|
Flanged Variant
|
ISO 7380-2 (Button head with integrated wide flange collar) | — |
|
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 |