UNC Screws / UNF Screws

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-Many special screw specifications that typically require custom manufacturing elsewhere are available as standard items from NBK.

What are Inch Screws (Unified Screws) ?

Inch screws (Unified screws) are fasteners manufactured with dimensions measured in inches, as opposed to metric screws, which are made using millimeters.
They are used in equipment and devices that conform to inch-based standards, including industrial machinery, aerospace equipment, digital devices, and telecommunications systems.
The Unified screw thread system includes two main types: UNC (Unified National Coarse) and UNF (Unified National Fine).
As a specialized manufacturer of custom screws, NBK offers an extensive lineup of inch screws.
Our lineup includes screws in various materials and configurations, as well as inch-standard nuts and hex keys.
Please make use of the “Product Finder” located on the left side of the screen.

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Part Name	Hex Socket Head Cap Screws - Inch Thread	Socket Head Cap Screws with Small Head (Inch Thread)	Socket Button Head Cap Screws - Inch Thread	Hexalobular Socket Head Cap Screws with Super Ultra Low Profile (Inch Thread)	Hexalobular Socket Head Cap Screws with Super Ultra Low Profile - Stainless Steel (Inch Thread)	Vented Inch Socket Head Cap Screws	Socket Head Cap Captive Screws (Inch Screws)	Inch Super Ultra Low Profile Hexalobular Socket Head Cap Screws with Nylon Patch	Inch Super Ultra Low Profile Hexalobular Socket Head Cap Screws with Nylon Patch
Part Number	SNSS(INCH)	SNSS-SD(INCH)	SNBS(INCH)	SET-TZB(INCH)	SETS(INCH)	SVSS(INCH)	SSC(INCH)	SET-TZB-ALK(INCH)	SETS-ALK(INCH)
Feature	Inch Thread	Small Head Space-saving	Inch Thread Button Head CapScrews	Hexalobular Socket Super Ultra Low Profile Space-saving Inch Screws	Hexalobular Socket Super Ultra Low Profile Space-saving Inch Screws	Inch Thread Socket Head Cap Screws	Inch Thread Captive / Loss Prevention	Hexalobular Socket Extra Low Profile Space-Saving Inch Screw Nylon Patch	Hexalobular Socket Extra Low Profile Space-Saving Inch Screw Nylon Patch
Material	SUSXM7 (Equivalent to SUS304)	SUSXM7 (Equivalent to SUS304)	Equivalent to SUS304	Steel	SUSXM7 (Equivalent to SUS304)	Equivalent to SUS304	SUSXM7 (Equivalent to SUS304)	Steel	SUSXM7 (Equivalent to SUS304)
Surface Treatment	-	-	-	Trivalent chromate treatment	-	-	-	Trivalent chromate treatment	-
Thread Size	No.4-40UNC ～ 3/8-16UNC	No.4-40UNC ～ 5/16-18UNC	No.4-40UNC ～ 1/4-20UNC	No.6-32UNC ～ No.10-32UNF	No.4-40UNC ～ No.10-32UNF	No.4-40UNC ～ 1/4-20UNC	No.4-40UNC ～ 1/4-20UNC	No.6-32UNC ～ No.10-32UNF	No.4-40UNC ～ No.10-32UNF
CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD
Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications
List	SNSS-#10-24 SNSS-#10-32 SNSS-#12-24 SNSS-#4-40 SNSS-#5-40 SNSS-#6-32 SNSS-#8-32 SNSS-1/4-20 SNSS-1/4-28 SNSS-3/8-16 SNSS-5/16-18	SNSS-#10-24-SD SNSS-#10-32-SD SNSS-#4-40-SD SNSS-#6-32-SD SNSS-#8-32-SD SNSS-1/4-20-SD SNSS-5/16-18-SD	SNBS-#10-24 SNBS-#10-32 SNBS-#4-40 SNBS-#5-40 SNBS-#6-32 SNBS-#8-32 SNBS-1/4-20	SET-#10-24-TZB SET-#10-32-TZB SET-#6-32-TZB SET-#8-32-TZB	SETS-#10-24 SETS-#10-32 SETS-#4-40 SETS-#6-32 SETS-#8-32	SVSS-#10-24 SVSS-#10-32 SVSS-#4-40 SVSS-#5-40 SVSS-#6-32 SVSS-#8-32 SVSS-1/4-20	SSC-#10-32 SSC-#4-40 SSC-#6-32 SSC-#8-32 SSC-1/4-20	SET-#10-24-TZB-ALK SET-#10-32-TZB-ALK SET-#6-32-TZB-ALK SET-#8-32-TZB-ALK	SETS-#10-24-ALK SETS-#10-32-ALK SETS-#4-40-ALK SETS-#6-32-ALK SETS-#8-32-ALK

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Part Name	Hex Nut for Inch Screw	Flat Washer for Inch Screw	Spring Washer for Inch Screw	Plastic Inch Socket Head Cap Screws - PEEK	Plastic Inch Socket Head Cap Screws - PEEK GF30	Plastic Inch Hex Head Screws - PEEK	Plastic Inch Cross Recessed Pan Head Machine Screws - PEEK	Plastic Inch Cross Recessed Pan Head Machine Screws - PEEK GF30	Plastic Inch Cross Recessed Pan Head Machine Screws - RENY
Part Number	SHNS(INCH)	SWAS-IF	SWAS-IS	SPE-C(INCH)	SPEG-C(INCH)	SPE-H(INCH)	SPE-P(INCH)	SPEG-P(INCH)	SPA-P(INCH)
Feature	For Inch Screws	For Inch Screws	For Inch Screws	Low Outgas Heat Resistance Chemical Resistance Electrical Insulation	Inch Threads High Strength High Specific Strength Heat Resistance Chemical Resistance Low Outgas Electrical Insulation	Low Outgas Heat Resistance Chemical Resistance Electrical Insulation	Low Outgas Heat Resistance Chemical Resistance Electrical Insulation	Inch Threads High Strength High Specific Strength Heat Resistance Chemical Resistance Low Outgas Electrical Insulation	Inch Threads High Strength High Specific Strength Lightweight
Material	Equivalent to SUS304	Equivalent to SUS304	Equivalent to SUS304	PEEK	PEEK GF30	PEEK	PEEK	PEEK GF30	RENY
Surface Treatment	-	-	-	-	-	-	-	-	-
Thread Size	No.4-40UNC ～ 3/8-16UNC	No.4-40UNC ～ 3/8-16UNC	No.4-40UNC ～ 3/8-16UNC	No.2-56UNC ～ 3/8-16UNC	No.2-56UNC ～ 1/4-20UNC	1/4-20UNC ～ 3/8-16UNC	No.2-56UNC ～ 1/4-20UNC	No.2-56UNC ～ 1/4-20UNC	No.2-56UNC ～ 1/4-20UNC
CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD
Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications
List	SHNS-#10-24 SHNS-#10-32 SHNS-#4-40 SHNS-#6-32 SHNS-#8-32 SHNS-1/4-20 SHNS-3/8-16 SHNS-5/16-18	SWAS-#10-IF SWAS-#4-IF SWAS-#6-IF SWAS-#8-IF SWAS-1/4-IF SWAS-3/8-IF SWAS-5/16-IF	SWAS-#10-IS SWAS-#4-IS SWAS-#6-IS SWAS-#8-IS SWAS-1/4-IS SWAS-3/8-IS SWAS-5/16-IS	SPE-#10-24-C SPE-#10-24-C(100) SPE-#10-32-C SPE-#10-32-C(100) SPE-#2-56-C SPE-#2-56-C(100) SPE-#4-40-C SPE-#4-40-C(100) SPE-#6-32-C SPE-#6-32-C(100) SPE-#8-32-C SPE-#8-32-C(100) SPE-1/4-20-C SPE-1/4-20-C(100) SPE-1/4-20-C(50) SPE-3/8-16-C SPE-3/8-16-C(50) SPE-5/16-18-C SPE-5/16-18-C(50)	SPEG-#10-32-C SPEG-#10-32-C(100) SPEG-#2-56-C SPEG-#2-56-C(100) SPEG-#4-40-C SPEG-#4-40-C(100) SPEG-#6-32-C SPEG-#6-32-C(100) SPEG-#8-32-C SPEG-#8-32-C(100) SPEG-1/4-20-C SPEG-1/4-20-C(100)	SPE-1/4-20-H SPE-1/4-20-H(100) SPE-1/4-20-H(50) SPE-3/8-16-H SPE-3/8-16-H(50) SPE-5/16-18-H SPE-5/16-18-H(50)	SPE-#10-24-P SPE-#10-24-P(100) SPE-#10-32-P SPE-#10-32-P(100) SPE-#2-56-P SPE-#2-56-P(100) SPE-#4-40-P SPE-#4-40-P(100) SPE-#6-32-P SPE-#6-32-P(100) SPE-#8-32-P SPE-#8-32-P(100) SPE-1/4-20-P SPE-1/4-20-P(100) SPE-1/4-20-P(50)	SPEG-#10-32-P SPEG-#10-32-P(100) SPEG-#2-56-P SPEG-#2-56-P(100) SPEG-#4-40-P SPEG-#4-40-P(100) SPEG-#6-32-P SPEG-#6-32-P(100) SPEG-#8-32-P SPEG-#8-32-P(100) SPEG-1/4-20-P SPEG-1/4-20-P(100)	SPA-#10-32-P SPA-#10-32-P(100) SPA-#10-32-P(200) SPA-#2-56-P SPA-#2-56-P(100) SPA-#2-56-P(1000) SPA-#4-40-P SPA-#4-40-P(100) SPA-#4-40-P(1000) SPA-#6-32-P SPA-#6-32-P(100) SPA-#6-32-P(1000) SPA-#8-32-P SPA-#8-32-P(100) SPA-#8-32-P(200) SPA-#8-32-P(500) SPA-1/4-20-P SPA-1/4-20-P(100)

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Part Name	Plastic Inch Slotted Pan Head Machine Screws - PEEK	Plastic Inch Slotted Flat Head Machine Screws - PEEK	Plastic Inch Hex Nuts - PEEK	Plastic Inch Hex Nuts - PC	Plastic Inch Hex Nuts - PC	Plastic Inch Threaded Rods - PC	Plastic Inch Threaded Rods - RENY	Hex Keys for Inch Screws
Part Number	SPE-PS(INCH)	SPE-FS(INCH)	SPE-N(INCH)	SPC-N(INCH)	SPC-N-WH(INCH)	SPC-Z(INCH)	SPA-Z(INCH)	SKH(INCH)
Feature	Low Outgas Chemical Resistance Heat Resistance Electrical Insulation	Low Outgas Chemical Resistance Heat Resistance Electrical Insulation	Low Outgas Heat Resistance Chemical Resistance Electrical Insulation	Electrical Insulation Lightweight Shock Resistance Weather Resistance	Electrical Insulation Lightweight Shock Resistance Weather Resistance	Electrical Insulation Lightweight Shock Resistance Weather Resistance	Inch Threads High Strength High Specific Strength Lightweight	For Inch Screws
Material	PEEK	PEEK	PEEK	PC	PC	PC	RENY	Steel
Surface Treatment	-	-	-	-	-	-	-	Ferrosoferric Oxide Film (Black)
Thread Size	No.4-40UNC ～ No.10-32UNF	No.4-40UNC ～ No.10-32UNF	No.4-40UNC ～ 1/4-20UNC	-	-	-	-	-
CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD	CAD
Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications	Specifications
List	SPE-#10-32-PS SPE-#10-32-PS(100) SPE-#4-40-PS SPE-#4-40-PS(100) SPE-#6-32-PS SPE-#6-32-PS(100) SPE-#8-32-PS SPE-#8-32-PS(100)	SPE-#10-32-FS SPE-#10-32-FS(100) SPE-#4-40-FS SPE-#4-40-FS(100) SPE-#6-32-FS SPE-#6-32-FS(100) SPE-#8-32-FS SPE-#8-32-FS(100)	SPE-#10-24-N SPE-#10-24-N(100) SPE-#10-32-N SPE-#10-32-N(100) SPE-#4-40-N SPE-#4-40-N(100) SPE-#6-32-N SPE-#6-32-N(100) SPE-#8-32-N SPE-#8-32-N(100) SPE-1/4-20-N SPE-1/4-20-N(100)	SPC-W3/8-N SPC-W3/8-N(200)	SPC-W3/8-N-WH SPC-W3/8-N-WH(200)	SPC-W3/8-Z	SPA-W3/8-Z	SKH-1/16 SKH-1/4 SKH-1/8 SKH-3/16 SKH-3/32 SKH-5/16 SKH-5/32 SKH-5/64 SKH-7/64 SKH-9/64

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This page introduces washers. As well as a description of washers, the washer products handled by NBK are introduced.

No. 6: Thermal Cycling

Here we discuss thermal cycling, which is often an issue in semiconductor manufacturing equipment.

Helpful Resources

SEMS Screws: Efficiency and Convenience in Fastening

Washers: Essential Components for Secure Connections

No. 6: Thermal Cycling

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Customization

Flexus【Muilti-Functional Machined Slotted Springs】

Designs and Examples of What NBK Can Create

Ball Rollers : Characteristics

Custom made

Cleanroom Wash / Cleanroom Packing Service

Screw Length Adjustment Service

Couplings Bore and Keyway Additional Modification Service

Captive Processing Service

Screw combination service

No. 6: Thermal Cycling

Washer fall-out prevention is required 【Workability/Maintenance】

Monitors need to be movable with one touch in accordance with the worker's height or the nature of the work【Improved productivity/workability】

Simple positioning with vertical axes is needed 【Workability / maintenance】

Moving the control panel of a machine tool horizontally【Workability & Maintenance】

Screw Size Chart: Comprehensive Guide to Metric Dimensions

Hexalobular Internal Driving Feature for Bolts and Screws

Unified Coarse Screw Threads/Unified Fine Screw Threads

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Slip Torque of Coupling – Set Screw Type

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Coupling and Single-axis Actuator Assembly Method

Hints for correctly using NBK products: Quick Positioning Brackets

Hints for correctly using NBK products: Captive Washer for Pull

Hints for correctly using NBK products: Metal Super Knob

Procedure of Selection

Choosing the most suitable coupling

Choosing the most suitable coupling

Procedure of Selection (Actuator)

Procedure of Selection

No. 6: Thermal Cycling

Washer fall-out prevention is required 【Workability/Maintenance】

Monitors need to be movable with one touch in accordance with the worker's height or the nature of the work【Improved productivity/workability】

Simple positioning with vertical axes is needed 【Workability / maintenance】

What are Captive Bolts (Screws)? Introduction of the NBK Captive Series

SEMS Screws: Efficiency and Convenience in Fastening

What are Captive Bolts (Screws)? Introduction of the NBK Captive Series

Description of Tamper Resistant Screws & Security Screws (Bolts) for the Engineers

No. 2: Vacuum environments

What are Hex Nuts?

What is Specific Strength? A new index for weight reduction of equipment 【Smaller and Lighter】

Preventing gaps between the sheet and screw when fastening thin sheets

Screws must be protected from chemicals 【Energy-saving / reduced work-hours】

Higher torque and Lower price.

NBK SPECIAL SCREWS

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Select Based on Application

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Solving common issues with Semiconductor Manufacturing Equipment（Pre-Process）

A new generation of disk couplings

No. 6: Thermal Cycling

Micro Screws: M0.6 (S0.6) to M2.6 Lineup

Miniature Screws/Precision Screws Lineup List

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What makes our custom screws special

Customization

NBK SPECIAL SCREWS

Flexus【Muilti-Functional Machined Slotted Springs】

Designs and Examples of What NBK Can Create

No. 6: Thermal Cycling

Select Based on Application

What is Specific Strength? A new index for weight reduction of equipment 【Smaller and Lighter】

No. 5: Solving common problems inside equipment

Solving common issues with Semiconductor Manufacturing Equipment（Pre-Process）

Washers: Essential Components for Secure Connections

What are Socket Head Cap Screws (Bolts) ?

Hexalobular Internal Driving Feature for Bolts and Screws

Simple positioning with vertical axes is needed 【Workability / maintenance】

Unified Coarse Screw Threads/Unified Fine Screw Threads

Washers: Essential Components for Secure Connections

No. 6: Thermal Cycling

What are Socket Head Cap Screws (Bolts) ?

Washer fall-out prevention is required 【Workability/Maintenance】

Hexalobular Internal Driving Feature for Bolts and Screws

Vol.6　Varieties of Screws "Beyond" SUS

Vol.1　What is Seizing (Galling)?

Vol.4　What are washers used for?

Vol.7　Screw Tightening Control Methods