McMaster-Carr logo
    Filter by
    System of Measurement
    Thread Size
    Industrial Info Compare
    Thread Pitch
    Industrial Info Snippet
    Attribute Image
    Thread Spacing
    Industrial Info Compare
    Nut Type
    Industrial Info Compare
    Hex Nut Profile
    Industrial Info Compare
    Fastener Strength Grade/Class
    Industrial Info Snippet
    Thread Type
    Industrial Info Compare
    Fastener Strength Rating
    Specifications Met
    Industrial Info Compare
    Thread Direction
    Thread Fit
    Industrial Info Snippet
    Attribute Image
    Drive Style
    Industrial Info Snippet
    U.S.–Mexico–Canada Agreement (USMCA) Qualifying
    DFARS Specialty Metals
    Industrial Info Compare
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Locking Type
    Pipe Size
    Industrial Info Snippet
    Fitting Connection
    Forward
    Enter e-mail addresses in the fields below
    Message
    Cancel
    Print
    How can we improve?
    Comments
    E-mail address (if you would like a response)
    6 Products
    About Hex Nuts
    industrial info icon

    Choose a hex nut with the right profile, material, and strength for your application.

    Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Hex Nuts.
    The most commonly used hex nuts, these are suitable for fastening most machinery and equipment.
    Medium-Strength Steel
    These Grade 5 or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread
    Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M56 × 3 mm8545Class 8DIN 9341000000000000000
    M56 × 4 mm8545Class 8DIN 934100000000000000
     

    Heavy-Profile Hex Nuts

    Image of Product. Front orientation. Hex Nuts. Heavy-Profile Hex Nuts.
    About 10% wider and taller than standard-profile hex nuts, these handle heavier loads by distributing them over a larger area.
    Extreme-Strength Steel
    These nuts are about 20% stronger than high-strength steel nuts. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M56 × 5.5 mm9056ASTM Grade 2H
    		ASTM A194
    		1000000000000000
     

    Thread Adapters for Drum Openings

    Image of Product. Bottom orientation. Thread Adapters. Thread Adapters for Drum Openings, Polypropylene, M56 Threads.
    Image of Product. Stainless Steel M56, M60, M64, M70, and BSPP. Front orientation. Thread Adapters. Thread Adapters for Drum Openings, 316 Stainless Steel.

    Polypropylene

    M56 Threads

    Stainless Steel

    M56, M60, M64,

    M70, and BSPP

    Convert drum openings with metric or BSPP threads to a 2 NPT pipe size.
    Inlet
    Outlet
    Pipe/Thread
    Size
    Gender
    Pipe
    Size
    Gender
    Seal Material
    Max. Temp.,
    ° F
    Each
    Polypropylene
    M56 MetricMale2 NPTFemaleViton® Fluoroelastomer
    		1200000000000000
     
    316 Stainless Steel
    M56 MetricMale2 NPTFemale—2500000000000000
     

    Locknuts for use with Cotter Pins

    Use these locknuts to secure rotating parts subjected to mild vibration, such as the wheels on carts and hand trucks. They’re not recommended for use on parts exposed to high vibration because the pin can shear under prolonged stress. These nuts are reusable, but you'll need a new cotter pin (not included) with each use.
    Medium-Strength Steel
    Image of ProductInUse. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    Image of Product. Front orientation. Locknuts. Locknuts for use with Cotter Pins.
    These Grade 5 or Class 8 nuts are your go-to for fastening most machinery and equipment. To avoid stripped threads during installation, make sure your screw has a comparable strength rating.
    Steel—Best for dry environments since moisture will cause these nuts to rust.
    Thread Size
    Wd.,
    mm
    Ht.,
    mm
    Fastener Strength
    Grade/Class
    For Cotter
    Pin Dia., mm
    Specs.
    Met
    Pkg.
    Qty.
    Pkg.
    Steel
    M56 × 5.5 mm8557Class 88DIN 9351000000000000000
     
    back to top