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    56 Products
    About Threaded Inserts
    industrial info icon

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

    Performance

    Performance

    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
     

    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
     
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