Socket Head Cap Screws

Socket head cap screws, commonly known as allen bolts or allen key bolts, represent a distinct category of screws engineered with a hexagonal (hex) internal drive embedded within the head. This unique design distinguishes them from conventional screws, as they are specifically crafted for tightening and loosening using an Allen key, as opposed to traditional screwdrivers. This hexagonal drive style sets socket screws apart from other popular screw head types such as Phillips head, slotted, flathead screws, and Pozidriv screws.

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Stainless Steel Socket Head Cap Screws (Allen Bolts) | Fixabolt®

Precision threads. Clean heads. Maximum grip.

Fixabolt® stainless steel socket head cap screws, also known as Allen bolts, are engineered for high-strength fastening where access is tight and a neat finish matters. Featuring a deep hex socket in the head, these screws are ideal for installation with Allen keys or hex drivers, delivering reliable torque and clean visuals in everything from machinery assembly to structural joints.

Manufactured to DIN 912 / ISO 4762 standards, our socket cap screws are a trusted choice for tradespeople, fabricators, and engineers across the UK.

Where Are Socket Head Cap Screws Used?

Socket cap screws are perfect when a standard hex head is too bulky, but strength and precision still matter.

They’re widely used in:

  • Machinery & mechanical assemblies
  • Brackets and fixings with limited space
  • Automotive & motorsport builds
  • Metal frameworks and fabrication
  • CNC assemblies and jigs
  • Timber-to-metal and precision joinery

Tighten confidently from the head side, even in recessed or hard-to-reach spots.

Cap Screws Grades & Sizes

Our socket head cap screws are available in A2 (304) stainless steel – ideal for general-purpose indoor and outdoor use

  • Diameters: M6 to M12
  • Lengths: 25mm to 200mm

Why Fixabolt® Socket Cap Screws?

✔ DIN 912 compliant for precise, clean fits
✔ Allen drive for easy installation in tight spaces
✔ Bulk discounts available for trade
✔ Tracked UK delivery with reliable stock

Need matching washers or nyloc nuts? We’ve got the stainless steel fixings to match.

Socket Cap Screws vs Other Hex Bolts

Unlike standard hex bolts or full thread set screws, socket cap screws are tightened using a hex key (Allen key) inserted into the head. This makes them ideal when:

  • You can’t access the sides of the fastener
  • You want a flush or recessed finish
  • You’re working in compact mechanical assemblies

Socket Head Cap Screws FAQs

Q: Are these DIN 912 socket screws?

Yes. All Fixabolt® socket cap screws are manufactured to DIN 912 or ISO 4762 standards.

Q: Are these the same as Allen bolts?

Yes. Allen bolts, hex socket screws, and socket cap screws are just different names for the same fastener.

Q: Can I use socket cap screws outdoors?

Absolutely. Our A2 stainless steel options are corrosion-resistant and suitable for external use.

Fixings built for engineers. Fixings made to last. That’s Fixabolt®.