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    29 Products
    About Threaded Inserts
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    Choose the right threaded insert for your application and learn how to install it securely.

    Closed-End Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.
    Image of Product. Shown In Cross Section. Side1 orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.

    Shown

    In

    Cross

    Section

    Keep threads clear and prevent leaks. These inserts have a closed end that blocks debris and fluids from entering parts. Keys drive into soft metal, such as aluminum, so they don’t slip or rotate in the hole. Comparable to Keensert inserts, they’re more secure than thread-locking 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.
    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
     
    18-8 Stainless Steel
    10-32
    		3/8"-16
    		0.563"Q
    		0.332"2MIL-I-4591493508A240000000———0
    1/4"-20
    		7/16"-14
    		0.625"X
    		0.397"2MIL-I-4591493508A2500000093904A525000000
    5/16"-18
    		1/2"-13
    		0.750"29/64"
    		0.453"4MIL-I-4591493508A2600000093904A53500000
    3/8"-16
    		9/16"-12
    		0.813"33/64"
    		0.516"4MIL-I-4591493508A2700000093904A54500000
    3/8"-24
    		9/16"-12
    		0.813"33/64"
    		0.516"4MIL-I-4591493508A28000000———0
     
    Thin Wall
     
    18-8 Stainless Steel
    2-56
    		8-32
    		0.250"29 Ga.
    		0.134"2MIL-I-4591493508A1100000093904A15000000
    4-40
    		10-32
    		0.313"20 Ga.
    		0.161"2MIL-I-4591493508A1200000093904A25000000
    6-32
    		12-28
    		0.375"3/16"
    		0.187"2MIL-I-4591493508A1300000093904A35000000
    8-32
    		1/4"-28
    		0.438"1 Ga.
    		0.228"2MIL-I-4591493508A1400000093904A45000000
    10-24
    		5/16"-18
    		0.500"I
    		0.272"2MIL-I-4591493508A1500000093904A60500000
    10-32
    		5/16"-18
    		0.500"I
    		0.272"2MIL-I-4591493508A16000000———0
    1/4"-20
    		3/8"-16
    		0.625"Q
    		0.332"2MIL-I-4591493508A1700000093904A61500000
    1/4"-28
    		3/8"-16
    		0.625"Q
    		0.332"2MIL-I-4591493508A18000000———0
    5/16"-18
    		7/16"-14
    		0.750"X
    		0.397"4MIL-I-4591493508A1900000093904A62500000
    5/16"-24
    		7/16"-14
    		0.750"X
    		0.397"4MIL-I-4591493508A21000000———0
    3/8"-16
    		1/2"-13
    		0.813"29/64"
    		0.453"4MIL-I-4591493508A2200000093904A63500000
    1/2"-13
    		5/8"-11
    		1.063"37/64"
    		0.578"4MIL-I-4591493508A2300000093904A64500000
     
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