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    30 Products

    Hex Nuts

    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Low-Strength Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. Hex Nuts.
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    3-48
    		3/16"1/16"ASME B18.2.210090480A00400000
     
    Corrosion-Resistant Stainless Steel
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. Hex Nuts.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    3-48
    		3/16"1/16"10091841A00400000
     
    Lightweight Aluminum
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. Hex Nuts.
    6061 Aluminum—One-third the weight of steel, these nuts are commonly used in robotics, automation, and other applications that have weight limitations. They're an alternative to stainless steel for rust resistance but are not as strong.
    Thread
    Size
    Wd.
    Ht.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    6061 Aluminum
    3-48
    		3/16"1/16"ASME B18.2.2590670A21300000
     
    Brass
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. Hex Nuts.
    Brass—Conductive and nonmagnetic, brass nuts are commonly used to secure electrical equipment, such as circuit board assemblies and mounting brackets, inside enclosures. They're also softer than most metals, so they won't damage other fastening components.
    Thread
    Size
    Wd.
    Ht.
    Pkg.
    Qty.
    Pkg.
    Brass
    3-48
    		3/16"1/16"10092671A00400000
     
    Plastic
    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    Image of Specification. Front orientation. Hex Nuts. Hex Nuts.
    Nylon 6/6— The most common plastic nuts, these are good for general purpose fastening. They are slippery and abrasion resistant, so they thread on smoothly and stand up to daily wear and tear. Nylon will swell and weaken when exposed to moisture, so these nuts are best for dry environments.
    Temp.,
    ° F
    Thread
    Size
    Wd.
    Ht.
    Min.
    Max.
    Choose a Color
    Pkg.
    Qty.
    Pkg.
    Nylon 6/6
    3-48
    		3/16"1/16"-40185Black, Off-White10094812A820000000
     

    Nylon-Insert Locknuts

    Image of Product. Front orientation. Locknuts. Nylon-Insert Locknuts.
    Versatile yet economical, these are the most commonly used locknuts. The nylon insert grips the screw to prevent loosening from moderate vibration without damaging threads. However, the insert may become brittle if exposed to high temperatures. These locknuts are reusable a handful of times, but the holding power decreases with each use.
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these locknuts are about half as strong as medium-strength steel nuts. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    Zinc-Plated Steel
    3-48
    		1/4"9/64"22010090631A00400000
     
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these locknuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Black-Oxide 18-8 Stainless Steel—Typically chosen for their appearance, these nuts have a dark, matte coating to create a finished look. They resist rust in wet and outdoor environments, but won't hold up to the harsh chemicals that 316 stainless steel can.
    Thread
    Size
    Wd.
    Ht.
    Insert Max.
    Temp., ° F
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    3-48
    		1/4"9/64"2202591831A00400000
     
    Black-Oxide 18-8 Stainless Steel
    3-48
    		1/4"9/64"2202594407A10900000
     

    Flange Nuts

    Image of Product. Front orientation. Flange Nuts. Flange Nuts.
    No need for a separate washer—these nuts have a plain flange that distributes pressure evenly for a wide variety of fastening applications. They are ideal for securing screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts. Also known as collar nuts.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Flange
    Thread
    Size
    Wd.
    Ht.
    Dia.
    Thk.
    Each
    18-8 Stainless Steel
    3-48
    		15/64"1/8"15/64"0.03"94758A20200000
     

    Cap Nuts

    Image of Product. Front orientation. Cap Nuts. Cap Nuts.
    Conceal and protect protruding screw threads while fastening parts together. These nuts help prevent damage to surrounding materials and reduce injuries. Also known as acorn nuts, they have a smooth, rounded head that creates a finished look.
    Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Pkg.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    3-48
    		5/64"1/4"1/4"191855A104000000000000000
     
    Low-Strength Steel
    Rated Grade 2, Class 6, or lower, these nuts are about half as strong as medium-strength steel nuts. They are suitable for light duty fastening applications, such as securing access panels. Use them with screws that have a similar strength rating to avoid stripping threads during installation.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    Pkg.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    Zinc-Plated Steel
    3-48
    		5/32"1/4"1/4"1091875A281000000000000000
     

    Press-Fit Nuts for Sheet Metal

    Image of Product. Front orientation. Press-Fit Nuts. Press-Fit Nuts for Sheet Metal.
    Image of Product. Bottom orientation. Press-Fit Nuts. Press-Fit Nuts for Sheet Metal.
    Add permanent threads to thin panels in seconds. The knurls on these clinch-style nuts deform and grip sheet metal to create a permanent hold. Push them into a drilled or punched hole with an arbor press around your workpiece to install—no messy welding required.
    Zinc-Plated Steel—A step up from plain steel, the zinc plating withstands occasional exposure to moisture.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust and mild chemicals.
    Head
    Thread
    Size
    Drill Bit
    Size
    For Min.
    Panel Thk.
    For Maximum Panel
    Hardness
    OD
    Ht.
    PEM® Part
    No.
    Head
    Shape
    Pkg.
    Qty.
    Pkg.
     
    Zinc-Plated Steel
    3-48
    		19 Ga.
    		0.04"Brinell 150, Rockwell B800.25"0.07"—Round2595185A301000000
     
    18-8 Stainless Steel
    3-48
    		19 Ga.
    		0.03"Brinell 125, Rockwell B700.25"0.07"CLS-348-0Round1096439A1500000
    3-48
    		19 Ga.
    		0.04"Brinell 125, Rockwell B700.25"0.07"CLS-348-1Round1096439A1700000
    3-48
    		19 Ga.
    		0.056"Brinell 125, Rockwell B700.25"0.07"CLS-348-2Round1096439A1110000
     

    Coupling Nuts

    Image of Product. Front orientation. Coupling Nuts. Coupling Nuts.
    Also known as extension nuts, these are commonly used to connect lengths of threaded rod and join threaded parts.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    1-9
    10-49
    50-Up
    18-8 Stainless Steel
    3-48
    		5/16"1/4"Fully Threaded90268A204000000000000000
     
    Brass
    Brass—With a warm, polished look, these nuts are often chosen for their appearance. Similar to 18-8 stainless steel, brass is corrosion resistant enough to stand up to wet environments. It is also softer than other metals, so it's easier to thread together.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Each
    Thread
    Size
    Lg.
    Wd.
    Threading
    1-9
    10-49
    50-Up
    Brass
    3-48
    		5/16"1/4"Fully Threaded90465A312000000000000000
     

    Flanged Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Flanged Knurled-Head Thumb Nuts.
    The slip-resistant head is easy to grip, while the flange distributes pressure evenly across the mounting surface without the need for a separate washer. These nuts are often used to secure screws in oversized or irregularly shaped holes since the flange covers a larger area than standard nuts.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Each
    18-8 Stainless Steel
    3-48
    		1/4"1/8"5/16"1/4"Fully Threaded95150A10300000
     
    Brass
    Brass—With a warm, polished look, these nuts are often chosen for their appearance. Similar to 18-8 stainless steel, brass is corrosion resistant enough to stand up to wet environments. It is also softer than other metals, so it's easier to thread together.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    Brass
    3-48
    		1/4"1/8"5/16"1/4"Fully Threaded192741A20200000
     

    Knurled-Head Thumb Nuts

    Image of Attribute. Front orientation. Contains Annotated. Thumb Nuts. Knurled-Head Thumb Nuts.
    Get a good grip on these nuts, even with oily fingers. They have a raised, slip-resistant head, so you can tighten them by hand and make controlled adjustments. Knurled-head nuts have a smaller profile than wing nuts, so they fit in tighter spots.
    Corrosion-Resistant Stainless Steel
    18-8 Stainless Steel—The choice for wet and outdoor environments, these nuts resist rust. However, they won't hold up to the harsh chemicals that 316 stainless steel can.
    Collar
    Thread
    Size
    Dia.
    Ht.
    Head
    Dia.
    Ht.
    Threading
    Pkg.
    Qty.
    Pkg.
    18-8 Stainless Steel
    3-48
    		1/4"1/4"1/2"3/8"Fully Threaded191833A10400000
     

    Helical Threaded Insert Assortments with Installation Tools

    Image of Product. Front orientation. Threaded Inserts. Helical Threaded Insert Assortments with Installation Tools.
    Repair damaged threads or create new ones. These convenient assortments include helical inserts, an installation tool for each thread size, a drill bit, and a tap. The inserts are also known as Heli-Coil inserts.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    No. of Inserts
    Included
    Includes
    Thread
    Spacing
    Drill Bit Size
    For Max. Hole Dia.
    Each
    Pronged
     
    18-8 Stainless Steel
    2881-64 Thread × 0.11" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    2-56 Thread × 0.129" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    3-48 Thread × 0.148" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    4-40 Thread × 0.168" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    6-32 Thread × 0.207" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    8-32 Thread × 0.246" Installed Lg. (24 Inserts and 24 Screw-Locking Inserts)
    Drill Bits
    Installation Tools
    Through-Hole Taps    		Coarse
    		5/64"
    3/32"
    36 Ga.
    31 Ga.
    26 Ga.
    17 Ga.
    		0.078"
    0.094"
    0.107"
    0.120"
    0.147"
    0.173"    		90285A1340000000
     

    Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Helical Threaded Inserts, Pronged.

    Pronged

    Restore, reinforce, or create threads in metal. The tough coils on these inserts expand once installed to anchor in a tapped hole. Also known as Heli-Coil inserts, they're often used in engine heads and machinery housings where strong connections are critical. Unlike threadlocking inserts, you can remove and reuse them without them losing their strength.
    Installation requires a drill bit, a helical insert tap, and an installation tool.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Prong
    Break-Off Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    3-48
    		0.099"7/64"
    		0.109"MS1221151091732A2050000091709A09900000091709A40400000090261A150000000092955A1010000000
    3-48
    		0.148"7/64"
    		0.109"MS1221551091732A207000091709A0990000091709A4040000090261A15000000092955A101000000
     
    Extraction Tools
    Remove installed helical inserts.
    For Pronged Helical Inserts—Place the tip into pronged inserts and lightly strike the tool’s head. Then, turn the tool counterclockwise with pressure to extract the insert.
    For Thread Size
    Each
    For Pronged Helical Inserts
    3-48, 3-56, 4-40, 4-48, 5-40, 5-44, 6-32, 6-40, 8-32, 8-36, 8-40, M2.5, M3, M3.5, M4
    		90254A310000000
     

    Screw-Locking Helical Threaded Inserts

    Image of Product. Pronged. Bottom orientation. Threaded Inserts. Screw-Locking Helical Threaded Inserts, Pronged.

    Pronged

    The irregularly shaped threads tightly grip screws to prevent them from loosening or backing out under vibration. Use these inserts to create or repair threads in pumps and other machinery that shakes and rattles. Also known as Heli-Coil inserts.
    Installation requires a drill bit, a helical insert tap, and an installation tool.
    Pronged—The prong attaches to an installation tool for precise control as you drive inserts in. Remove the prong with a punch or break-off tool before inserting a screw.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Through-Hole
    Taps
    Closed-End
    Hole Taps
    Installation
    Tools
    Prong
    Break-Off Tools
    Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Each
    Each
    Each
    Each
    Pronged
     
    18-8 Stainless Steel
    3-48
    		0.099"7/64"
    		0.109"MS21209C0310, NASM21209590296A1840000091709A09900000091709A40400000090261A150000000092955A1010000000
    3-48
    		0.148"7/64"
    		0.109"MS21209C0315, NASM212091090296A098000091709A0990000091709A4040000090261A15000000092955A101000000
     
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