Button Socket Cap Screws

Button socket cap screws or dome head socket screws offer aesthetic and functional benefits, making them a popular choice for applications where a smooth, rounded head is preferable. Their low-profile, dome-shaped design provides a secure and neat finish. Nickel Systems delivers a variety of button socket cap screws, including those made from exotic, corrosion-resistant materials, such as Inconel® and titanium.

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Specifications & Technical Data

Nickel Systems stocks the button head cap screws needed for your next project. Use our specifications and technical data sheets to select the size of your specific fastener. We also accommodate custom requests, providing specialty materials, sizes and coatings upon request.

Download our Button Head Cap Screw Dimensioning Table

Dimensions


Nominal Size	A		H		S	J	T	F
	Head Diameter		Head Height		Head Side Height	Hex Socket Size	Key Engagement	Fillet Transition Diameter
	Max	Min	Max	Min	Ref	Nom	Min	Max	Min
4	0.213	0.201	0.059	0.051	0.015	1/16	0.035	0.132	0.122
6	0.262	0.250	0.073	0.063	0.015	5/64	0.044	0.158	0.148
8	0.312	0.298	0.087	0.077	0.015	3/32	0.052	0.194	0.184
10	0.361	0.347	0.101	0.091	0.020	1/8	0.070	0.220	0.210
1/4	0.437	0.419	0.132	0.122	0.031	5/32	0.087	0.290	0.280
5/16	0.547	0.527	0.166	0.152	0.031	3/16	0.105	0.353	0.343
3/8	0.656	0.636	0.199	0.185	0.031	7/32	0.122	0.415	0.405
1/2	0.875	0.851	0.265	0.245	0.046	5/16	0.175	0.560	0.540
5/8	1.000	0.970	0.331	0.311	0.062	3/8	0.210	0.685	0.665
3/4	1.125	1.105	0.375	0.355	0.062	7/16	0.245	0.740	0.720

Button Socket Cap Screw Specifications

Standard (ASME/ANSI)
- ASME B18.3-1998
Metric (IFI)

Three Blue Hexagons Are Lined Up On A White Background

What Are Socket Screws?

Socket screws are a class of threaded fasteners with a hexagonal recess in the head, designed to be driven with an Allen wrench or hex key. The internal hex drive provides reliable torque for more efficient tightening and loosening compared to traditional screw types. They are ideal for use in compact or confined spaces because the internal drive eliminates the need for external tool clearance.

Key Characteristics

Socket screws are characterized by features such as:

Internal hexagonal socket drive
A cylindrical, flat or dome-shaped head
High clamping force within limited spaces
Fully or partially threaded configurations

Common Types

Socket screws come in several variations:

Low-head socket cap screws
Flat socket cap screws
Socket head shoulder screws
Socket set screws
Vented socket screws

What Are Button Socket Cap Screws?

Button socket cap screws are a type of socket screw featuring a distinctive rounded, low-profile head. Button socket cap screws are favored for their practicality and aesthetic appeal, making them ideal for use when the screw head is visible outside the assembly. Additionally, they are selected when clearance is restricted and a socket drive is necessary. However, it’s important to note that due to their sleek design, button sockets may not handle as much stress as socket head cap screws, as their heads are comparatively smaller.

Other Names

Button socket cap screws are also known by different names:

Socket dome head screws
Button head hex screws
Button head Allen screws
Dome head socket screws
Button socket screws
Round head socket screws

Industries and Applications

Button head Allen screws offer dependable performance and a visually appealing finish across multiple industries, including:

Automotive

Automotive applications leverage the durability and compact design of button socket cap screws to secure components that need to remain functional and visually appealing.

Applications: Interior trims, engine cover panels, door panels and vehicle frames
Materials: Stainless steel, aluminum alloys

Machinery

In machinery applications, button socket cap screws secure machine components where exposed fasteners require a combination of strength and smooth edges to prevent snagging or injury.

Applications: Equipment covers, guards and CNC machines
Materials: Alloy A286, Hastelloy®, Carpenter® 20, Inconel®

Electronics

In electronics, button socket screws provide the necessary strength for secure connections while maintaining a clean, professional appearance.

Applications: Equipment housings, audio/video equipment
Materials: Stainless steel, aluminum alloys

Tips for Purchasing Button Socket Cap Screws

Keep the following best practices in mind to ensure you select the right fastener for your project:

Dimension verification: Confirm critical dimensions such as the nominal diameter, thread pitch and length using our detailed specification guide.
Material selection: Choose a material that aligns with the environmental conditions and mechanical requirements of your application.
Finish considerations: Consider suitable coatings or finishes if the screw will be exposed to environmental stressors like moisture, chemicals or extreme temperatures.
Torque requirements: Verify that the fastener can handle the necessary torque for your application without risking damage to the screw or assembly. Consider that button socket cap screws have slightly lower capacities than standard socket screws.

Get High-Performance Button Socket Cap Screws From Nickel Systems

Button socket cap screws offer a high-strength, low-profile solution for applications where performance and appearance matter. Nickel Systems provides a comprehensive selection of button socket cap screws to meet the needs of numerous industries. We support the successful outcomes of your projects with expert consultations, fast shipping and a wide range of exotic materials in stock. Contact us today to request a quote.

Industries We Serve

Nickel Systems provides high quality exotic grade materials that hold up in the toughest, most severe heat and corrosive environments. With our large inventory of specialty fasteners in stock, we are always ready to answer the call to serve the most challenging applications.