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    64 Products

    Screw-On Caps

    Image of Product. Front orientation. Protective Caps. Screw-On Caps, Aluminum.

    Aluminum

    Thread onto male pipe and fittings for the most secure fit. These caps keep dust, paint, and coatings out of threads and pipe. They also protect from damage during manufacturing, shipping, and storage.
    Aluminum—Use aluminum caps instead of steel to prevent corrosion from spreading to aluminum pipe and tubing.
    Thread
    Size
    Type
    For OD
    Inside
    Ht.
    Flexibility
    Max. Temp.,
    ° F
    Mil. Spec.
    Pkg.
    Qty.
    Pkg.
    Aluminum
     
    For Straight-Thread Fittings
    5/16"-24
    		UNF
    		5/16"21/64"Rigid650MIL-C-5501/3503522T11000000
    3/8"-24
    		UNF
    		3/8"19/64"Rigid650MIL-C-5501/3503522T1200000
    7/16"-20
    		UNF
    		7/16"15/32"Rigid650MIL-C-5501/3503522T130000
    1/2"-20
    		UNF
    		1/2"7/16"Rigid650MIL-C-5501/3503522T1400000
    9/16"-18
    		UNF
    		9/16"15/32"Rigid650MIL-C-5501/3503522T1500000
    5/8"-18
    		UNF
    		5/8"33/64"Rigid650MIL-C-5501/3503522T1600000
    3/4"-16
    		UNF
    		3/4"35/64"Rigid650MIL-C-5501/3503522T1700000
    7/8"-14
    		UNF
    		7/8"21/32"Rigid650MIL-C-5501/3503522T1800000
    1 1/16"-12
    		UN
    		1 1/16"49/64"Rigid650MIL-C-5501/3253522T1900000
    1 5/16"-12
    		UN
    		1 5/16"49/64"Rigid650MIL-C-5501/3253522T2100000
    1 5/8"-12
    		UN
    		1 5/8"23/32"Rigid650MIL-C-5501/3103522T2200000
     

    Metal Round Caps

    Image of Product. Front orientation. Protective Caps. Metal Round Caps.
    Tougher than plastic and rubber caps for best protection from impact and wear. These caps cover pipe ends to prevent damage and keep out dust and debris during shipping and storage.
    Aluminum—Use aluminum caps instead of steel to prevent corrosion from spreading to aluminum pipe and tubing.
    Aluminum
    For OD
    For Pipe
    Size
    Inside
    Ht.
    Flexibility
    Max.
    Temp.
    Each
    35/64"1/4
    		7/16"RigidNot Rated9275K11200000
    43/64"3/8
    		9/16"RigidNot Rated9275K1220000
    27/32"1/2
    		7/16"RigidNot Rated9275K1320000
    1"—23/32"RigidNot Rated9275K1420000
    1 3/64"3/4
    		5/8"RigidNot Rated9275K1520000
    1 1/4"—3/4"RigidNot Rated9275K1620000
    1 5/16"1
    		11/16"RigidNot Rated9275K1720000
    1 1/2"—21/32"RigidNot Rated9275K1820000
    1 21/32"1 1/4
    		13/16"RigidNot Rated9275K1920000
    1 29/32"1 1/2
    		15/16"RigidNot Rated9275K310000
    2"—1 7/32"RigidNot Rated9275K2120000
    2 1/4"—1 1/16"RigidNot Rated9275K2230000
    2 3/8"2
    		1 1/16"RigidNot Rated9275K320000
    2 1/2"—1 5/16"RigidNot Rated9275K2320000
    2 7/8"2 1/2
    		1 3/8"RigidNot Rated9275K330000
    3"—1 1/8"RigidNot Rated9275K2520000
    3 1/2"3
    		1 3/8"RigidNot Rated9275K3400000
    4"3 1/2
    		1 1/2"RigidNot Rated9275K3500000
    4 1/2"4
    		1 7/8"RigidNot Rated9275K3600000
    5 9/16"5
    		1 7/8"RigidNot Rated9275K27200000
    6 5/8"6
    		1 7/8"RigidNot Rated9275K3700000

    Screw-In Plugs for Pipe and Tubing

    Threaded for the most secure fit on female pipe and fittings. These plugs protect from damage during shipping and storage. They also keep dust, paint, and coatings from blocking holes and threads.
    For Straight-Thread Fittings
    Image of Product. Front orientation. Contains Annotated. Protective Plugs. Screw In, For Round Holes, For Pipe, For Round Shapes, For Straight-Thread Fittings, Aluminum.

    Aluminum

    Aluminum—Withstand the highest temperatures of all our pipe and tubing plugs. They’re more wear resistant than plastic but won’t hold up as well to chemicals.
    Thread
    Size
    Type
    For Tube
    OD
    Ht.
    Max. Temp.,
    ° F
    Pkg.
    Qty.
    Pkg.
    Aluminum
    5/16"-24
    		UNF
    		5/32"11/32"650253438T16000000
    3/8"-24
    		UNF
    		3/16"9/32"650253438T1700000
    7/16"-20
    		UNF
    		1/4"9/32"650253438T180000
    1/2"-20
    		UNF
    		5/16"5/16"650253438T190000
    9/16"-18
    		UNF
    		3/8"5/16"650253438T210000
    5/8"-18
    		UNF
    		3/8"5/16"650253438T220000
    3/4"-16
    		UNF
    		1/2"7/16"650253438T2300000
    7/8"-14
    		UNF
    		5/8"1/2"650253438T2400000
    1 1/16"-12
    		UN
    		3/4"15/32"650253438T2500000
    1 5/16"-12
    		UN
    		1"7/16"650253438T2600000
    1 7/8"-12
    		UN
    		1 1/2"5/8"65053438T2700000
     
    For 37° Flared Tube
    Image of Product. Front orientation. Contains Annotated. Protective Plugs. Screw In, For Round Holes, For Pipe, For Round Shapes, For 37° Flared Tube, Aluminum.

    Aluminum

    Aluminum—Withstand the highest temperatures of all our pipe and tubing plugs. They’re more wear resistant than plastic but won’t hold up as well to chemicals.
    Thread
    Size
    Type
    For Tube
    OD
    Ht.
    Max. Temp.,
    ° F
    Pkg.
    Qty.
    Pkg.
    Aluminum
    3/8"-24
    		UNF
    		3/16"3/8"650253438T33000000
    7/16"-20
    		UNF
    		1/4"15/32"650503438T3400000
    1/2"-20
    		UNF
    		5/16"15/32"650503438T3500000
    9/16"-18
    		UNF
    		3/8"1/2"650503438T3600000
    5/8"-18
    		UNF
    		3/8"1/2"650253438T3700000
    3/4"-16
    		UNF
    		1/2"19/32"650503438T3800000
    7/8"-14
    		UNF
    		5/8"11/16"650253438T3900000
    1 1/16"-12
    		UN
    		3/4"21/32"650253438T4100000
    1 5/16"-12
    		UN
    		1"23/32"650103438T4200000
    1 7/8"-12
    		UN
    		1 1/2"7/8"65053438T4300000
     

    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.
    Lightweight Aluminum
    2011 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.
    Pkg.
    Thread
    Size
    Thread
    Dp.
    Wd.
    Ht.
    Pkg.
    Qty.
    1-9
    10-49
    50-Up
    2011 Aluminum
    6-32
    		3/16"5/16"19/64"1091884A213000000000000000000
    10-24
    		5/32"3/8"11/32"2591884A21600000000000000
    10-32
    		5/32"3/8"11/32"2591884A21900000000000000
    1/4"-20
    		5/32"7/16"3/8"2591884A2240000000000000
    5/16"-18
    		7/32"9/16"7/16"1091884A227000000000000
    3/8"-16
    		1/4"5/8"1/2"1091884A23500000000000000
     

    Fully-Threaded Standoff Caps

    Image of System. Front orientation. Standoff Caps. Fully-Threaded Standoff Caps.
    Image of Product. Bottom orientation. Standoff Caps. Fully-Threaded Standoff Caps.
    Give open-ended standoffs a finished look and protect them from dirt and debris.
    Aluminum—Aluminum caps have good corrosion resistance, are lightweight, and are nonmagnetic.
    Material
    Ht.
    Thread
    Lg.
    Choose a Thread Size
    Each
     
    For 1/4" Standoff OD
    Aluminum
    		1/4"3/8"4-40, 6-32, 8-32, 10-3293558A71500000
     

    Metal Square Plugs

    Image of Product. Front orientation. Contains Annotated. Protective Plugs. Metal Square Plugs.
    Designed to finish off the ends of square metal tubing, these plugs cover rough edges and block dirt and debris. Push into place and then drive with a hammer to secure.
    Aluminum—For aluminum tubing, use these plugs instead of steel to avoid rust that spreads when different metals are in contact.
    For
    Inside
    Head
    Lg.
    Wd.
    Ht.
    Lg.
    Wd.
    Each
    Aluminum
    0.77"0.77"1/2"1"1"2990N23000000
    1.02"1.02"5/8"1 1/4"1 1/4"2990N2200000
    1.27"1.27"13/16"1 1/2"1 1/2"2990N2400000
    1.77"1.77"3/4"2"2"2990N2500000
     
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