McMaster-Carr logo
    Filter by
    Thread Direction
    System of Measurement
    Mount Type
    Color
    DFARS Specialty Metals
    Export Control Classification Number (ECCN)
    Industrial Info Snippet
    Maximum Temperature
    Minimum Temperature
    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)
    14 Products

    Left-Hand Threaded-Stud Knobs

    Image of Product. Style 1. Front orientation. Style 1. Left-Hand Threaded-Stud Knobs, Knurled-Head Grip.
    Image of Product. Style 2. Front orientation. Style 2. Left-Hand Threaded-Stud Knobs, Ribbed Grip.
    Image of Product. Style 3. Front orientation. Four-Arm Grip. Left-Hand Threaded-Stud Knobs, Style 3.
    Image of Product. Style 4. Front orientation. Four-Arm Grip. Left-Hand Threaded-Stud Knobs, Style 4.

    Style 1

    Style 2

    Style 3

    Style 4

    Knobs have left-hand threads; they're used in applications where counterclockwise motion can loosen common right-hand threads. Mount them into a threaded hole to position, tighten, and hold fixtures, equipment, and machinery.
    Style 1—Knurled-Head Grip
    Image of Product. Style 1. Front orientation. Style 1. Left-Hand Threaded-Stud Knobs, Knurled-Head Grip.

    Style 1

    Black-Oxide Steel—Steel knobs have a black-oxide finish for mild rust resistance.
    303 Stainless Steel—303 stainless steel knobs have excellent corrosion resistance, making them the best choice for harsh environments. They also have good chemical resistance.
    Head
    Hub
    Each
    Thread
    Size
    Stud
    Lg.
    Dia.
    Ht.
    Dia.
    Ht.
    Stud Material
    1-9
    10-Up
    Black-Oxide Steel
    1/4"-20
    		1 3/4"1"1/4"5/8"1/2"Steel00000000000000000
    3/8"-16
    		1 3/4"1 1/2"5/16"3/4"11/16"Steel00000000000000000
     
    303 Stainless Steel
    1/4"-20
    		1 3/4"1"1/4"5/8"1/2"Stainless Steel00000000000000000
    5/16"-18
    		1 3/4"1"1/4"5/8"1/2"Stainless Steel00000000000000000
    3/8"-16
    		1 3/4"1 1/2"5/16"3/4"11/16"Stainless Steel00000000000000000
     
    Style 2—Ribbed Grip
    Image of Product. Style 2. Front orientation. Style 2. Left-Hand Threaded-Stud Knobs, Ribbed Grip.

    Style 2

    Phenolic—Phenolic knobs are a lightweight alternative to metal. They resist oil, grease, and solvents.
    Head
    Hub
    Each
    Thread
    Size
    Stud
    Lg.
    Dia.
    Ht.
    Dia.
    Ht.
    Stud
    Material
    Temp. Range,
    ° F
    1-9
    10-Up
    Black Phenolic
    1/4"-20
    		9/16"7/8"3/8"5/8"1/8"Steel-30 to 40000000000000000000
    1/4"-20
    		9/16"1 1/2"3/8"11/16"3/8"Steel-30 to 400000000000000000
    1/4"-20
    		3/4"1 1/4"3/8"5/8"3/8"Steel-30 to 400000000000000000
     
    Style 3—Four-Arm Grip
    Image of Product. Style 3. Front orientation. Four-Arm Grip. Left-Hand Threaded-Stud Knobs, Style 3.

    Style 3

    Phenolic—Phenolic knobs are a lightweight alternative to metal. They resist oil, grease, and solvents.
    Head
    Hub
    Each
    Thread
    Size
    Stud
    Lg.
    Dia.
    Ht.
    Dia.
    Ht.
    Stud
    Material
    Temp. Range,
    ° F
    1-9
    10-Up
    Black Phenolic
    1/4"-20
    		1"1 1/2"1/2"5/8"1/2"Steel-30 to 40000000000000000000
    3/8"-16
    		1"2"1/2"7/8"1/2"Steel-30 to 4000000000000000000
     
    Style 4—Four-Arm Grip
    Image of Product. Style 4. Front orientation. Four-Arm Grip. Left-Hand Threaded-Stud Knobs, Style 4.

    Style 4

    Aluminum—Aluminum knobs have mild corrosion resistance, are lightweight, and are nonmagnetic.
    Head
    Hub
    Each
    Thread
    Size
    Stud
    Lg.
    Dia.
    Ht.
    Dia.
    Ht.
    Stud
    Material
    1-9
    10-Up
    Aluminum
    1/4"-20
    		1 3/4"1 1/2"3/8"5/8"1/2"Steel0000000000000000000
    5/16"-18
    		1 3/4"2"3/8"3/4"5/8"Steel00000000000000000
    3/8"-16
    		1 3/4"2"3/8"3/4"5/8"Steel00000000000000000
    1/2"-13
    		1 3/4"2 1/2"1/2"1 1/8"1"Steel00000000000000000
     
    back to top