UNC Screws / UNF Screws

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

Latest

No. 2: Vacuum environments

Vacuum technology is often used in semiconductor manufacturing equipment. A vacuum is not required for all equipment. A vacuum would mainly be required for equipment that uses plasma or an electron beam. In Part 2, we introduce some NBK products that are ideal for use in these vacuum environments!

Description of Tamper Resistant Screws for the Engineers

This is the page on tamper-resistant screws in "Description of Special Screws for Designers." We introduce here what tamper-resistant screws are, the advantages of their use, various usage examples, and their types and characteristics.

Galling and Seizing

This is a phenomenon that occurs while tightening, where the surface of the screw thread melts or welds due to frictional heat and the screw stops moving. To resolve galling, NBK's special surface treatment screws, such as those with fluorine coating, are recommended.

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

NBK offers a wide-ranging lineup of small-diameter screws in various shapes and materials.
Various head diameters and heights are available for the same screw diameters, contributing to saving space.

Helpful Resources

No. 2: Vacuum environments

Description of Tamper Resistant Screws for the Engineers

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

No. 6: Thermal Cycling

Miniature Screws/Precision Screws Lineup List

Customization

Flexus

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

Galling and Seizing

No. 6: Thermal Cycling

Increased degree of vacuum in equipment is required 【Productivity increase】

Select the best screws for your needs

Select Based on Application

Slip Torque of Coupling – Set Screw Type

Property of High Performance Stainless Steel Screws

Plastic Screw Property

Vol.4 What are washers used for?

Hexagon Socket Head Cap Screws Excerpts from ISO 4762：2004, JIS B 1176:2015

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

Hints for correctly using NBK products: Ball Plungers

Procedure of Selection

Choosing the most suitable coupling

Choosing the most suitable coupling

Procedure of Selection (Actuator)

Procedure of Selection

No. 2: Vacuum environments

Galling and Seizing

No. 6: Thermal Cycling

Increased degree of vacuum in equipment is required 【Productivity increase】

What is a Coupling? Explanation of Types and Characteristics

No. 2: Vacuum environments

Description of Tamper Resistant Screws for the Engineers

SEMS Screws: Efficiency and Convenience in Fastening

What are Hex Nuts?

Theft Prevention 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

What is a Coupling? Explanation of Types and Characteristics

Select Based on Application

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

Vol.6 Varieties of Screws "Beyond" SUS

A new generation of disk couplings

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

No. 6: Thermal Cycling

Miniature Screws/Precision Screws Lineup List

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

What are low profile screws? Find advantages, disadvantages, and usage examples explained here!

What makes our custom screws special

Customization

NBK SPECIAL SCREWS

Flexus

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）

No. 2: Vacuum environments

Description of Tamper Resistant Screws for the Engineers

Galling and Seizing

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

Miniature Screws/Precision Screws Lineup List

No. 2: Vacuum environments

Description of Tamper Resistant Screws for the Engineers

Galling and Seizing

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

No. 6: Thermal Cycling

Vol.4　What are washers used for?

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