1/4-20 Button Head Socket Cap Screws Allen Bolts 18-8 Stainless All Lengths+Qty for Sale

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1/4-20 Button Head Socket Cap Screws Allen Bolts 18-8 Stainless All Lengths+Qty For Sale

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1/4-20 Button Head Socket Cap Screws Allen Bolts 18-8 Stainless All Lengths+Qty:
$11.99

1/4"-20 Stainless Steel Button Head Socket Cap Screws 18-8 (304)

Internal Hex (Allen) • Multi-Length • UNC Coarse • Bulk

Description

Fastenio 1/4"-20 button head socket cap screws in 18-8 (304) stainless steel. The low-profile button head sits ~25% lower than a standard socket head cap screw, giving a cleaner finished look while still accepting a 5/32" hex (Allen) key for driving. ASME B18.3 dimensions throughout.

This listing covers 1/4"-20 UNC Coarse only, in twenty lengths from 1/4" through 5", in pack quantities from 5 (sample) up to 2,500 (production bulk).

When to Use a Button Head SCS

Low-profile look — when you want a clean rounded finish on the visible side without a flush countersink.
Snag-free assemblies — the rounded crown reduces snag risk on equipment with frequent operator contact.
Internal drive — hex (Allen) drive resists cam-out under high torque and works in tight clearances where a wrench wouldn't fit.
Trade-off vs SHCS — lower clamp force capability than a standard socket head cap screw because the head is shorter. For maximum clamp load, see the cross-linked SHCS (Allen) listing.

Material

Grade: 18-8 Stainless Steel (Type 304 / A2-70 equivalent). Excellent corrosion resistance in atmospheric, freshwater, marine, and most chemical environments.

Finish: Plain (no plating). 18-8 forms a self-renewing passive oxide layer for natural corrosion protection.

Specification: ASME B18.3 button head socket cap screw dimensions.

How to Order

Select your variation by Length and Unit Quantity:

Length — measured under-head to tip. 1/4" is the shortest stock length; 5" the longest.
Drive: 5/32" hex (Allen) key for all 1/4"-20 button head SCS.
Pack Quantity — 5 and 10 are sample/repair packs. 25–100 cover small projects. 250–2,500 are production-volume bulk.

Built for repeat buyers. Clean listings, accurate item specifics, fast US shipping, and responsive support before and after the sale.

Need it faster? UPS 2nd Day Air and Next Day Air are available by request — message us with your ZIP code before purchase for a quote.

Need a larger quantity? Volume pricing is available beyond the listed pack sizes — message us with your target qty and we'll quote.

Bolt Specs at a Glance

Specifications below apply to every length variation. ASME B18.3 max dimensions; actual measurements may be slightly under (manufactured to tolerance).

Thread Size1/4-20 UNC (Coarse) Thread CoverageFully Threaded — all 20 length variations (1/4" through 5") Head StyleButton Head (low-profile dome) Head Diameter (A)0.437" max Head Height (H)0.140" max Drive TypeInternal Hex (Allen / Hex Socket) Drive Size5/32" hex key Available Lengths1/4" to 5" — 20 sizes (select via Item Length dropdown) Material & GradeStainless Steel 18-8 (Type 304 / A2-70 equivalent) FinishPlain (passive oxide layer) StandardASME B18.3

Applications

Marine — boat fittings, deck hardware (18-8 resists salt-water corrosion).
HVAC — equipment mounts, condensation-exposed connections.
Industrial — machinery assembly, equipment frames, custom fixtures.
Automotive — trim, interior brackets, exposed assemblies where appearance matters.
Construction — brackets, hardware, signage.
Signs & Outdoor — signage, lighting fixtures, decorative metalwork.

Notes

Torque: follow standard torque specs for 18-8 stainless 1/4"-20 (typically ~76 in-lb dry). 18-8 is softer than alloy steel — do not over-torque.
Galling prevention: use stainless-safe anti-seize for repeated assembly.
Compared to SHCS: button head has lower clamp force capacity than a standard socket head cap screw of the same diameter. For high-clamp applications, see the cross-linked SHCS listing.
Pair with: 1/4"-20 finished hex nut + 1/4" flat washer (cross-linked below) for through-bolting.

Related Fastenio Products

1/4-20 SS Socket Head Cap Screws

Standard SHCS (Allen) for higher clamp force.

View →

SS Finished Hex Nuts (Multi-Size)

1/4-20 hex nuts for through-bolting.

View →

SS Flat Washers 18-8

1/4" flat washer for load distribution.

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