Imperial Fasteners to Metric Size Conversion

Here's a handy chart when comparing imperial size fasteners in inches with metric sizes in millimetres

1/8" 3/16" 1/4" 5/16" 3/8" 7/16" 1/2" 9/16" 5/8" 11/16" 3/4" 13/16" 7/8" 15/16" 1
1.59mm 3.18mm 4.76mm 6.35mm 7.94mm 9.53mm 11.11mm 12.70mm 14.92mm 15.88mm 17.46mm 19.05mm 20.64mm 22.23mm 23.81mm 25.40mm

Imperial Nuts

Imperial Full Nut

Imperial Full Nuts

Imperial Hexagon Full Nuts UNC, UNF, BSW, & BSF.

Imperial Lock Nut

Imperial Half/Lock Nuts

Imperial Half Nuts, BSW, BSF, UNC, UNF Lock Nuts.

Imperial Nyloc Nuts

SW, BSF, UNC, UNF. Secure, vibration-resistant.

Imperial Castle Nuts

Castle & Slotted Nuts Imperial Sizes SW, BSF, UNC, UNF

Imperial Flange Nuts

For increased surface grip and stability.

Imperial Left Hand Nuts

Imperial Left Hand Nuts, BSW, BSF, UNC/UNF Left Hand Lock Nuts

Imperial Grade 10/12 Full Nuts

Hardened for automotive, structural, high temperature.

Imperial Grade 10 Nylon Nuts

Secure, vibration-resistant inch nylon nuts

Imperial Stainless Nuts

For high corrosion resistance. Full range of types available.

Imperial Vee Lock Nuts

AKA Imperial Stover Nuts, Internal Flange & Serrated Bottom.

Imperial Weld Nuts

Designed Specifically for Welding Applications.

Imperial Brass Nuts

Great for high temperature applications.

Imperial Bolts

Imperial HT Bolt Sets

As a set, High-tensile strength for demanding load-bearing.

Imperial HT Bolts

High-tensile strength for demanding load-bearing.

Imperial Flange Sets

Flange head for even distribution & reduced slippage.

Imperial Socket CSK 

Low-profile, flush fit with Allen-wrench engagement.

Imperial Socket Buttons

Rounded head, deep socket for reliable fastening.

Imperial Socket Caps

Designed for flush, secure, and clean installations.

Imperial Cup Sq Bolts

Secure fastening with a square neck for anti-rotation.

Imperial Socket Sets

For precise fastening in varied applications.

Imperial UNC/UNF Bolt Sets

Unified thread standards ensuring precise and robust fit. As a set

Imperial UNC/UNF Bolts

Unified thread standards ensuring precise and robust fit .

Imperial Cotter Pins

Secure mechanical components and prevent loosening.

Imperial Hex Keys

 Tool for engaging imperial hexagonal socket fasteners.

Imperial Machine Screws

Precision thread for consistent metal-metal fastening.

Imperial U Bolts

U-shaped for securing pipes, conduits, or anchoring.

Imperial Self Tappers

 Sharp, self-drilling screws metal or wood penetration.

Imperial Engineer Studs

Double-ended thread fasteners for assemblies.

Imperial Flange Bolts

Flange head for even distribution & reduced slippage.

Imperial Wood Screws

Tapered, sharp thread for reliable wood-wood fastenings.

Imperial Studding

Threaded bar rod for versatile fastening & extension.

Imperial Washers

Imperial Rect Spring Washer

Rectangular section, split design for consistent tension.

Imperial SQ Spring

Square section for optimal tension and fit.

Imperial BS3410 Table 3 Light

Compliant with tolerances for lightweight applications.

Imperial BS3410 Table 3 Heavy

Diagonal for precise alignment & angular seating.

Imperial BS3410 Table 1 Small

Specific tolerances for compact applications.

Imperial F436 Washers

Hardened flat washers for structural steel bolting.

Imperial BS3410 Table 4 Light

Precision-crafted, set tolerances for lighter applications.

Imperial BS3410 Table 4 Heavy

Tailored for high-stress; meeting stringent tolerances.

Imperial BS3410 Table 2 Large

Specific tolerances for compact applications.

Imperial ASA B27.1 1965 HVY

Washers conforming to American Standards Association.

Imperial Double Coil Rect Spring

Specific tolerances for compact applications.

Imperial ASA B27.1 1965 REG

Cut and deformed to prevent loosening of the assembly.

Imperial Repair Washers

Fixing and restoring strength to damaged areas.

Imperial BS3410 Table 6

Washers designed for specialized applications with set tolerances.

Imperial BS3410 Table 5

Engineered to meet standards for heavy-duty applications.

Imperial Phosphor Bronze

Corrosion-resistant, high-strength washers.

Imperial Thru Hard Washers

Heat-treated, hardened for durable & reliable fastening.

Imperial BS3410 Table 7

For specific requirements & specialized applications.

Imperial Stainless Washers

Corrosion-resistant, durable and long-lasting fastening.

Imperial Brass Washer

Corrosion-resistant, conductive & decorative use. DIN 125.

A full range of coatings and finishes.

Standard Finish Special Electroplating High Corrosion Resistance Automotive & Petrochemical Other Finishes
Self Colour-Plain COLBOLT HOT DIP GALVANISED DACROMET CHEMICAL BLACK
Bright ZINC & CLEAR CR3 TIN SHERARDIZED XYLAN BLACK JAPAN
Bright ZINC & YELLOW NICKEL RILSAN JS
Bright ZINC & BLACK BRASS SHERAPLEX DELTA TONE
BRIGHT ZINC & DE-EMBRITTLE DELTA PROTECT
MECHANICAL ZINC PTFE

Our Machining Processes

Standard Fasteners

Bolts, Screws, Washers, Nuts, Fixings & Much More

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Special Fasteners

Huge Range of Special Machining, Finishes & Coatings.

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Fixings & Resin

High quality fixings, resin and resin accessories & cartridge systems. 

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Nord-Lock

The wedge-locking technology to secures bolted joints

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Allthread

For when standard bolts are not long enough.

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BeamClamp & Boxbolt

Secure fixing  methods for structural steel.

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Construction

Large range of specialist construction fasteners.

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FastClamp

Handrails, safety barriers and guardrail systems 

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