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    100 Products
    About Threaded Inserts
    industrial info icon

    Choose the right threaded insert for your application and learn how to install it securely.

    Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal.
    These inserts are manufactured and tested to meet or compare to strict standards adopted by the U.S. military. The keys drive into aluminum and other soft metal for a secure hold that won't slip or rotate, even in vibrating vehicle or aerospace parts. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    Extra-Thick Wall—Stronger than standard- and thin-wall inserts, use them to reduce the size of tapped holes or replace threads that have been drilled out.
    High-Strength Cadmium-Plated Alloy Steel—These inserts have the strength to stand up to high-pressure applications and a plating that helps screws thread in smoothly.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Standard Wall
     
    High-Strength Cadmium-Plated Alloy Steel
    10-32
    		3/8"-16
    		0.313"Q
    		0.332"2MS51831A201, NAS1395-395101A104000000———0
    1/4"-28
    		7/16"-14
    		0.375"X
    		0.397"2MS51831A202, NAS1395-495101A1140000———0
    5/16"-24
    		1/2"-13
    		0.438"29/64"
    		0.453"4MS51831A20395101A1260000———0
    3/8"-24
    		9/16"-12
    		0.500"33/64"
    		0.516"4MS51831A20495101A1270000———0
    7/16"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51831A205, NAS1395-795101A1290000———0
    1/2"-20
    		11/16"-11
    		0.688"41/64"
    		0.641"4MS51831A206, NAS1395-895101A13200000———0
    9/16"-18
    		13/16"-16
    		0.813"49/64"
    		0.766"4MS51831A207, NAS1395-995101A13300000———0
    5/8"-18
    		7/8"-14
    		0.875"53/64"
    		0.828"4MS51831A20895101A13500000———0
    3/4"-16
    		1 1/8"-12
    		1.125"1 1/16"
    		1.062"4MS51831A20995101A13700000———0
     
    18-8 Stainless Steel
    10-32
    		3/8"-16
    		0.313"Q
    		0.336"2MS51831-201, NAS1395C393904A5120000———0
    1/4"-28
    		7/16"-14
    		0.375"X
    		0.401"2MS51831-202, NAS1395C493904A5220000———0
    5/16"-24
    		1/2"-13
    		0.438"29/64"
    		0.457"4MS51831-203, NAS1395C593904A5320000———0
    3/8"-24
    		9/16"-12
    		0.500"33/64"
    		0.521"4MS51831-204, NAS1395C693904A5420000———0
    7/16"-20
    		5/8"-11
    		0.625"37/64"
    		0.583"4MS51831-205, NAS1395C793904A2290000———0
    1/2"-20
    		11/16"-11
    		0.688"41/64"
    		0.646"4MS51831-206, NAS1395C893904A23200000———0
    9/16"-18
    		13/16"-16
    		0.813"49/64"
    		0.771"4MS51831-207, NAS1395C993904A23600000———0
    5/8"-18
    		7/8"-14
    		0.875"53/64"
    		0.833"4MS51831-208, NAS1395C1093904A24100000———0
    3/4"-16
    		1 1/8"-12
    		1.125"1 1/16"
    		1.067"4MS51831-20993904A24500000———0
    7/8"-14
    		1 1/4"-12
    		1.250"1 3/16"
    		1.192"4MS51831-21093904A24900000———0
    1"-12
    		1 3/8"-12
    		1.375"1 5/16"
    		1.317"4MS51831-21193904A2540000093904A7530000000
     
    Thin Wall
     
    High-Strength Cadmium-Plated Alloy Steel
    10-32
    		5/16"-18
    		0.313"I
    		0.272"2MS51830A201, NAS1394-395101A1110000———0
    1/4"-28
    		3/8"-16
    		0.375"Q
    		0.332"2MS51830A202, NAS1394-495101A1130000———0
    5/16"-24
    		7/16"-14
    		0.438"X
    		0.397"4MS51830A203, NAS1394-595101A1160000———0
    3/8"-24
    		1/2"-13
    		0.500"29/64"
    		0.453"4MS51830A204, NAS1394-695101A1180000———0
    7/16"-20
    		9/16"-12
    		0.563"33/64"
    		0.516"4MS51830A205, NAS1394-795101A1210000———0
    1/2"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51830A206, NAS1394-895101A1230000———0
     
    18-8 Stainless Steel
    4-40
    		12-24
    		0.250"14 Ga.
    		0.183"2NAS1395C0493904A211000093904A25600000
    10-32
    		5/16"-18
    		0.313"I
    		0.276"2MS51830-201, NAS1394C393904A6120000———0
    1/4"-28
    		3/8"-16
    		0.375"Q
    		0.336"2MS51830-202, NAS1394C493904A6220000———0
    5/16"-24
    		7/16"-14
    		0.438"X
    		0.401"4MS51830-203, NAS1394C593904A2140000———0
    3/8"-24
    		1/2"-13
    		0.500"29/64"
    		0.457"4MS51830-204, NAS1394C693904A2150000———0
    7/16"-20
    		9/16"-12
    		0.563"33/64"
    		0.521"4MS51830-205, NAS1394C793904A2160000———0
    1/2"-20
    		5/8"-11
    		0.625"37/64"
    		0.583"4MS51830-206, NAS1394C893904A2170000———0
     
    Extra-Thick Wall
     
    18-8 Stainless Steel
    10-32
    		7/16"-14
    		0.313"X
    		0.401"2MS51832-20193904A2190000093904A75600000
    1/4"-28
    		1/2"-13
    		0.375"29/64"
    		0.457"4MS51832-20293904A22100000———0
    5/16"-24
    		9/16"-12
    		0.438"33/64"
    		0.521"4MS51832-20393904A22300000———0
    3/8"-24
    		5/8"-11
    		0.500"37/64"
    		0.583"4MS51832-20493904A2250000093904A26700000
    1/2"-20
    		13/16"-16
    		0.688"49/64"
    		0.771"4MS51832-20693904A2330000093904A27700000
    9/16"-18
    		7/8"-14
    		0.813"53/64"
    		0.833"4MS51832-20793904A23700000———0
    5/8"-18
    		1"-12
    		0.875"15/16"
    		0.942"4MS51832-20893904A2420000093904A28600000
     

    Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal.
    Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    Dry-Film-Lubricated Cadmium-Plated Steel—The plating creates a barrier against rust.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Standard Wall
     
    Dry-Film-Lubricated Cadmium-Plated Steel
    10-32
    		3/8"-16
    		0.313"Q
    		0.332"2MS51831A201L, NAS1395-3L97255A247000000
    5/16"-24
    		1/2"-13
    		0.438"29/64"
    		0.453"4MS51831A203L97255A25100000
    3/8"-24
    		9/16"-12
    		0.500"33/64"
    		0.516"4MS51831A204L97255A25300000
    7/16"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51831A205L97255A25500000
    1/2"-20
    		11/16"-11
    		0.688"41/64"
    		0.641"4MS51831A206L97255A25700000
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    10-32
    		3/8"-16
    		0.313"Q
    		0.332"2NAS1395C3L97255A1320000
    1/4"-28
    		7/16"-14
    		0.375"X
    		0.397"2NAS1395C4L97255A1340000
    5/16"-24
    		1/2"-13
    		0.438"29/64"
    		0.453"4NAS1395C5L97255A1360000
    3/8"-24
    		9/16"-12
    		0.500"33/64"
    		0.516"4NAS1395C6L97255A1380000
    1/2"-20
    		11/16"-11
    		0.688"41/64"
    		0.641"4NAS1395C8L97255A14300000
    7/8"-14
    		1 1/4"-12
    		1.375"1 3/16"
    		1.188"4MS51831-210L97255A15200000
     
    Thin Wall
     
    Dry-Film-Lubricated Cadmium-Plated Steel
    10-32
    		5/16"-18
    		0.313"I
    		0.272"2MS51830A201L, NAS1394-3L97255A2320000
    1/4"-28
    		3/8"-16
    		0.375"Q
    		0.332"2MS51830A202L, NAS1394-4L97255A2340000
    1/4"-28
    		7/16"-14
    		0.375"X
    		0.397"2MS51831A202L, NAS1395-4L97255A23500000
    3/8"-24
    		1/2"-13
    		0.500"29/64"
    		0.453"4MS51830A204L, NAS1394-6L97255A2390000
    1/2"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51830A206L, NAS1394-8L97255A24400000
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    10-32
    		5/16"-18
    		0.313"I
    		0.272"2MS51830-201L, NAS1394C3L97255A1170000
    1/4"-28
    		3/8"-16
    		0.375"Q
    		0.332"2MS51830-202L, NAS1394C4L97255A1190000
    5/16"-24
    		7/16"-14
    		0.438"X
    		0.397"4MS51830-203L, NAS1394C5L97255A1220000
    3/8"-24
    		1/2"-13
    		0.500"29/64"
    		0.453"4MS51830-204L, NAS1394C6L97255A1240000
    7/16"-20
    		9/16"-12
    		0.563"33/64"
    		0.516"4MS51830-205L, NAS1394C7L97255A12600000
    1/2"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51830-206L, NAS1394C8L97255A12800000
     

    Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Key-Locking Threaded Inserts for Soft Metal.
    Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Standard Wall—Stronger than thin-wall inserts, these are your go-to choice for threading most holes.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    High-Strength High-Temperature A286 Stainless Steel—High temperatures won't reduce the load capacity of these inserts. They also resist chemicals such as bleach and chlorine.
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Standard Wall
     
    High-Strength High-Temperature A286 Stainless Steel
    10-32
    		3/8"-16
    		0.313"Q
    		0.332"2MS51831CA20193509A250000000
    1/4"-28
    		7/16"-14
    		0.375"X
    		0.397"2MS51831CA20293509A27000000
    5/16"-24
    		1/2"-13
    		0.438"29/64"
    		0.453"4MS51831CA20393509A28000000
    3/8"-24
    		9/16"-12
    		0.500"33/64"
    		0.516"4MS51831CA20493509A31000000
    5/8"-18
    		7/8"-14
    		0.875"53/64"
    		0.828"4MS51831CA20893509A32000000
     
    Thin Wall
     
    High-Strength High-Temperature A286 Stainless Steel
    1/4"-28
    		3/8"-16
    		0.375"Q
    		0.332"2MS51830CA20293509A17000000
    5/16"-24
    		7/16"-14
    		0.438"X
    		0.397"4MS51830CA20393509A18000000
    3/8"-24
    		1/2"-13
    		0.500"29/64"
    		0.453"4MS51830CA20493509A21000000
    1/2"-20
    		5/8"-11
    		0.625"37/64"
    		0.578"4MS51830CA20693509A23000000
     

    Mil. Spec. Rivet-Mount Nuts

    Image of ProductInUse. Front orientation. Contains Annotated. Rivet-Mount Nuts.
    Image of Product. Bottom orientation. Rivet-Mount Nuts.
    Image of Attribute. Front orientation. Contains Annotated.
    Image of Attribute. Top orientation. Contains Annotated.
    Create threads in hard-to-work areas—where you can’t reach the back of a workpiece, or material is too thin to be tapped. For a strong grip, these rivet-mount nuts have distorted threads that increase friction with bolts. Because they mount with two rivets, they won’t spin when you’re tightening screws. However, these nuts do move inside their retainers, which lets you install bolts at a slight angle; use them to align with off-center parts. All meet military guidelines for dimensions and material.
    Cadmium-Plated Carbon Steel and Cadmium-Plated Steel—Cadmium-plated nuts resist corrosion in industrial and saltwater environments, although they will lose their corrosion resistance over 450° F. The cadmium plating also adds lubricity, making these nuts easy to install.
    A286 Stainless Steel—A286 stainless steel nuts are corrosion resistant.
    Silver-Plated A286 Stainless Steel—Silver-plated stainless steel nuts withstand temperatures up to 800° F. The silver plating also adds lubricity and prevents seizing caused by friction between nuts and bolts.
    Lubricated—Lubricated nuts thread onto bolts smoothly.
    Base
    Barrel
    Mounting
    Thread
    Size
    Lg.
    Wd.
    Thk.
    Dia.
    Ht.
    No. of
    Holes
    Hole
    Dia.
    Hole
    Ctr.-to-Ctr.
    Mil.
    Spec.
    Certificate Type
    Each
    Steel—Unlubricated
    10-32
    		47/64"13/32"3/32"0.234"5/32"20.098"1/2"MS21075-3N—90857A12900000
    1/4"-28
    		51/64"1/2"3/32"0.313"3/16"20.098"9/16"MS21075-4N—90857A1300000
     
    Carbon Steel—Unlubricated
    10-32
    		61/64"13/32"1/32"0.234"7/32"20.098"11/16"MS21059-3—90857A1030000
    1/4"-28
    		1 19/64"33/64"1/32"0.313"1/4"20.098"1"MS21059-4—90857A1040000
     
    Cadmium-Plated Carbon Steel—Lubricated
    10-32
    		61/64"13/32"1/32"0.234"7/32"20.098"11/16"MS21059L3—90857A1090000
    1/4"-28
    		1 19/64"33/64"1/32"0.313"1/4"20.098"1"MS21059L4—90857A1100000
    5/16"-24
    		1 19/64"39/64"3/64"3/8"9/32"20.13"1"MS21059L5—90857A1110000
    3/8"-24
    		1 19/64"43/64"1/16"0.453"19/64"20.13"1"MS21059L6Material Certificate
    		90857A11200000
     
    Cadmium-Plated Steel—Lubricated
    10-32
    		47/64"13/32"3/32"0.234"5/32"20.098"1/2"MS21075L3N—90857A1340000
    1/4"-28
    		51/64"1/2"3/32"0.313"3/16"20.098"9/16"MS21075L4N—90857A1350000
     
    A286 Stainless Steel—Lubricated
    10-32
    		47/64"13/32"3/32"0.234"5/32"20.098"1/2"MS21076L3NMaterial Certificate
    		90857A1440000
    10-32
    		61/64"13/32"1/32"0.234"7/32"20.098"11/16"MS21060L3—90857A1220000
    1/4"-28
    		51/64"1/2"3/32"0.313"3/16"20.098"9/16"MS21076L4N—90857A14500000
    1/4"-28
    		1 19/64"33/64"1/32"0.313"1/4"20.098"1"MS21060L4—90857A12300000
    5/16"-24
    		1 1/64"37/64"7/64"0.391"7/32"20.13"23/32"MS21076L5N—90857A14600000
    5/16"-24
    		1 19/64"39/64"3/64"3/8"9/32"20.13"1"MS21060L5—90857A12400000
    3/8"-24
    		1 19/64"43/64"1/16"0.453"19/64"20.13"1"MS21060L6Material Certificate
    		90857A12500000
     
    Silver-Plated A286 Stainless Steel—Unlubricated
    10-32
    		47/64"13/32"3/32"0.234"5/32"20.098"1/2"MS21076-3N—90857A1380000
    10-32
    		61/64"13/32"1/32"0.234"7/32"20.098"11/16"MS21060-3—90857A1160000
    1/4"-28
    		51/64"1/2"3/32"0.313"3/16"20.098"9/16"MS21076-4NMaterial Certificate
    		90857A13900000
    1/4"-28
    		1 19/64"33/64"1/32"0.313"1/4"20.098"1"MS21060-4—90857A11700000
    5/16"-24
    		1 1/64"37/64"7/64"0.391"7/32"20.13"23/32"MS21076-5NMaterial Certificate
    		90857A14000000
     
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