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    76 Products
    About Pipe and Fittings
    industrial info icon

    Measure your pipe and fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

    Low-Pressure Stainless Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Stainless Steel Threaded Pipe Locknuts.
    Use these locknuts in a low-pressure pipe line.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPTF (Dryseal) threads and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    304 Stainless Steel—304 stainless steel locknuts have very good corrosion resistance.
    316 Stainless Steel—316 stainless steel locknuts have excellent corrosion resistance.
    ANSI/MSS SP-114—Locknuts that meet ANSI/MSS SP-114 adhere to high-quality standards for heat treating, material thickness, and marking.
    For Pipe
    For
    Flange
    304
    Stainless Steel
    316
    Stainless Steel
    Pipe
    Size
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Fabrication
    Schedule
    Material
    Class
    Material
    Specs. Met
    Each
    Each
    NPSL Female
    1/8
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58100000———0
    1/8
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67100000
    1/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K5820000———0
    1/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K6720000
    3/8
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58300000———0
    3/8
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67300000
    1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58400000———0
    1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67400000
    3/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58500000———0
    3/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67500000
    1
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58600000———0
    1
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67600000
    1 1/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58700000———0
    1 1/4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67700000
    1 1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58800000———0
    1 1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67800000
    2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K58900000———0
    2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K67900000
    2 1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K59100000———0
    2 1/2
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K68100000
    3
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K59200000———0
    3
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K68200000
    4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K59300000———0
    4
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K68300000
     

    Low-Pressure Brass and Bronze Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Brass and Bronze Threaded Pipe Locknuts.
    Use these locknuts in low-pressure flow applications. They have good corrosion resistance.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    NSF/ANSI 61—Locknuts rated for use with drinking water meet NSF/ANSI 61 safety standards.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Specs. Met
    Food Industry
    Std.
    Each
    NPSL Female
    1/8
    		1/2"3/16"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K12100000
    1/4
    		21/32"1/4"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K1220000
    3/8
    		49/64"9/32"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K1230000
    1/2
    		31/32"5/16"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K1240000
    3/4
    		1 15/64"11/32"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K1250000
    1
    		1 1/2"3/8"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K12600000
    1 1/4
    		1 55/64"27/64"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K12700000
    1 1/2
    		2 1/8"15/32"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K12800000
    2
    		2 5/8"17/32"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K12900000
    2 1/2
    		3 3/4"9/16"200 psi @ 72° FAir, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B16.15—4429K46400000
    3
    		4 1/4"5/8"200 psi @ 72° FAir, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B16.15—4429K46500000
     

    High-Pressure Brass Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. High-Pressure Brass Threaded Pipe Locknuts.
    These locknuts have the strength to handle high-pressure applications. They are brass for good corrosion resistance.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Material
    Fabrication
    Each
    NPSL Female
    1/8
    		11/16"3/16"1,000 psi @ 72° FAir, Natural Gas, Oil, WaterBrassMachined50785K14100000
    1/4
    		7/8"1/4"1,000 psi @ 72° FAir, Natural Gas, Oil, WaterBrassMachined50785K1420000
    3/8
    		1"5/16"1,000 psi @ 72° FAir, Natural Gas, Oil, WaterBrassMachined50785K1430000
    1/2
    		1 1/8"1/4"1,000 psi @ 72° FAir, Natural Gas, Oil, WaterBrassMachined50785K1440000
    3/4
    		1 3/8"21/64"1,000 psi @ 72° FAir, Natural Gas, Oil, WaterBrassMachined50785K1450000
     

    Low-Pressure Aluminum Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Aluminum Threaded Pipe Locknuts.
    In addition to being lightweight, these aluminum locknuts offer good corrosion resistance. Use them in low-pressure flow applications. To prevent cracking, do not tighten more than a 1/4-turn past hand tight.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Each
    NPSL Female
    1/4
    		15/16"5/32"150 psi @ 72° FAir, Oil, Water150
    		6061 Aluminum40
    		Aluminum125
    		Aluminum44705K41200000
    3/8
    		1 1/8"3/16"150 psi @ 72° FAir, Oil, Water150
    		6061 Aluminum40
    		Aluminum125
    		Aluminum44705K4130000
    1/2
    		1 3/8"1/4"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K4140000
    3/4
    		1 5/8"5/16"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K41500000
    1
    		2"3/8"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K41600000
    1 1/4
    		2 3/8"7/16"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K41700000
    1 1/2
    		2 3/4"1/2"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K41800000
    2
    		3 3/8"5/8"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K41900000
    2 1/2
    		3 3/4"3/4"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K33100000
    3
    		4 1/2"15/16"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K33200000
     

    Low-Pressure Iron and Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Iron and Steel Threaded Pipe Locknuts.
    Use these locknuts for low-pressure applications in noncorrosive environments.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPTF (Dryseal) threads, NPSC (National Pipe Straight Coupling) threads, and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    Pipe
    Size
    Hex Wd.
    Lg.
    Max. Pressure
    @ Temp.
    Max. Steam
    Pressure @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    For Flange
    Material
    Specs. Met
    Each
    NPSL Female
    1/8
    		11/16"3/16"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Steel40
    		SteelIron, SteelASME B16.1444605K43300000
    1/4
    		27/32"1/4"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Steel40
    		SteelIron, SteelASME B16.1444605K4340000
    3/8
    		1"9/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2110000
    1/2
    		1 3/16"5/16"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2120000
    3/4
    		1 7/16"11/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2130000
    1
    		1 3/4"3/8"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21400000
    1 1/4
    		2 3/32"27/64"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2150000
    1 1/2
    		2 11/32"15/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21600000
    2
    		2 7/8"17/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21700000
     

    Low-Pressure Galvanized Iron and Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Galvanized Iron and Steel Threaded Pipe Locknuts.
    The galvanized finish on these locknuts provides fair corrosion resistance. Locknuts are for use in low-pressure applications.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex Wd.
    Lg.
    Max. Pressure
    @ Temp.
    Max. Steam
    Pressure @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Specs. Met
    Each
    NPSL Female
    1/4
    		27/32"1/4"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K61200000
    3/8
    		1"0.28"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K6130000
    1/2
    		1 3/16"0.31"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K6140000
    3/4
    		1 7/16"0.34"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K6150000
    1
    		1 3/4"0.38"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K61600000
    1 1/4
    		2 3/32"0.42"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K61700000
    1 1/2
    		2 11/32"0.47"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K61800000
    2
    		2 7/8"0.53"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K61900000
     

    Conduit Locknuts

    Secure threaded conduit fittings to knockouts. These locknuts keep fittings from shifting, so connections stay stable and wiring is protected inside electrical boxes or enclosures.
    For Metal and Plastic Fittings
    Image of Product. Front orientation. Conduit and Fittings. Conduit Locknuts, For Metal and Plastic Fittings.
    316 Stainless Steel—Our most corrosion-resistant fittings won't degrade when exposed to salt water and harsh chemicals.
    Pipe
    Size
    Specs. Met
    Each
    NPSL Thread
     
    316 Stainless Steel
    1/2
    		C-UL Listed, UL Listed7513K317000000
    3/4
    		C-UL Listed, UL Listed7513K31800000
    1
    		C-UL Listed, UL Listed7513K31900000
    1 1/4
    		C-UL Listed, UL Listed7513K41100000
    1 1/2
    		C-UL Listed, UL Listed7513K41200000
    2
    		C-UL Listed, UL Listed7513K41300000
    3
    		C-UL Listed, UL Listed7513K15200000
    4
    		C-UL Listed, UL Listed7513K15300000
     
    Conduit Locknut and Reaming Pliers
    Image of Product. Front orientation. Conduit Locknut and Reaming Pliers.
    Tighten locknuts and ream both the inside and outside of conduit with one tool. These pliers have combination jaws with multiple curved openings to work with 1/2" (13 mm) and 3/4" (19 mm) EMT conduit locknuts and 1/2" rigid conduit locknuts and flat nuts. Their machined nose fits snugly into locknut wings. They can also pull wire and fish tape, thanks to their serrated jaws. Pliers have plastic grips for comfort.
    Jaw
    Overall
    Lg.
    Max.
    Cap.
    Lg.
    Opening
    Style
    Texture
    Material
    For Tape
    Shape
    With Wire
    Cutter
    Each
    Combination Jaw and Cushion Grip
    7 3/4"1 3/8"1 5/8"ManualSerratedSteelFlatNo4642N11000000
     
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