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    31 Products

    Countersunk Tooth Lock Washers

    These washers grip flat- and oval-head countersunk screws, so you get a secure hold without overtightening. They resist loosening in applications with constant motion, such as conveyors. Tooth lock washers typically can't be reused because the teeth often get bent when tightened.
    External Tooth
    Image of Product. Front orientation. Lock Washers. Countersunk Washer, Tooth Washer, External Tooth.
    Teeth on the outside edge bite into both the screw head and the mating surface to lock the assembly in place. 
    Wear-Resistant 400 Series Stainless Steel—These grip hard material better than other types of stainless steel. They are not as corrosion resistant as 18-8 and 316 stainless steel, so they are best for environments that experience occasional moisture.
    Zinc-Plated Steel—A common choice for areas with occasional exposure to moisture.
    Black-Oxide Steel—Typically chosen for their appearance, these washers have a dark, matte coating that creates a finished look. They offer minimal corrosion resistance, so they're best for dry environments.
    DIN 6798—Best for slightly bumpy or irregular surfaces because the teeth are angled to make even contact with the material.
    For Screw
    Size
    ID
    OD
    Thk.
    Countersink
    Angle
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    Wear-Resistant 400 Series Stainless Steel
    No. 6
    0.140"0.289"0.017" to 0.021"82°
    ASME B18.21.110000000000000000
    No. 8
    0.167"0.322"0.017" to 0.021"82°
    ASME B18.21.110000000000000000
    No. 10
    0.195"0.354"0.020" to 0.025"82°
    ASME B18.21.1250000000000000
    No. 12
    0.220"0.421"0.020" to 0.025"82°
    ASME B18.21.1500000000000000
    1/4"
    0.255"0.454"0.020" to 0.025"82°
    ASME B18.21.1250000000000000
    5/16"
    0.318"0.599"0.023" to 0.028"82°
    ASME B18.21.1250000000000000
     
    Zinc-Plated Steel
    No. 4
    0.113"0.213"0.015" to 0.019"82°
    ASME B18.21.15000000000000000
    No. 6
    0.140"0.289"0.017" to 0.021"82°
    ASME B18.21.110000000000000000
    No. 8
    0.167"0.322"0.017" to 0.021"82°
    ASME B18.21.110000000000000000
    No. 10
    0.195"0.354"0.020" to 0.025"82°
    ASME B18.21.15000000000000000
    No. 12
    0.220"0.421"0.020" to 0.025"82°
    ASME B18.21.110000000000000000
    1/4"
    0.255"0.458"0.022"82°
    ASME B18.21.110000000000000000
    5/16"
    0.318"0.599"0.023" to 0.028"82°
    ASME B18.21.110000000000000000
    3/8"
    0.383"0.765"0.028" to 0.034"82°
    ASME B18.21.12500000000000000
    1/2"
    0.512"0.976"0.037" to 0.045"82°
    ASME B18.21.1100000000000000
    M3
    3.2 mm6.0 mm0.2 mm to 0.3 mm90°
    DIN 67981000000000000000
    M4
    4.3 mm8.0 mm0.2 mm to 0.3 mm90°
    DIN 67981000000000000000
    M5
    5.3 mm9.8 mm0.3 mm to 0.4 mm90°
    DIN 6798500000000000000
    M6
    6.4 mm11.8 mm0.4 mm to 0.5 mm90°
    DIN 679850000000000000
    M8
    8.4 mm15.3 mm0.4 mm to 0.5 mm90°
    DIN 6798500000000000000
    M10
    10.5 mm19.0 mm0.5 mm to 0.6 mm90°
    DIN 679825000000000000
    M12
    13.0 mm23.0 mm0.5 mm to 0.6 mm90°
    DIN 6798250000000000000
     
    Black-Oxide Steel
    No. 4
    0.113"0.213"0.015" to 0.019"82°
    ASME B18.21.1250000000000000
    No. 6
    0.140"0.289"0.017" to 0.021"82°
    ASME B18.21.12500000000000000
    No. 8
    0.167"0.322"0.017" to 0.021"82°
    ASME B18.21.1250000000000000
    No. 10
    0.195"0.354"0.020" to 0.025"82°
    ASME B18.21.1250000000000000
    No. 12
    0.220"0.421"0.020" to 0.025"82°
    ASME B18.21.1250000000000000
    1/4"
    0.255"0.454"0.020" to 0.025"82°
    ASME B18.21.1250000000000000
    5/16"
    0.318"0.599"0.023" to 0.028"82°
    ASME B18.21.1250000000000000
    3/8"
    0.383"0.765"0.028" to 0.034"82°
    ASME B18.21.1250000000000000
    1/2"
    0.512"0.976"0.037" to 0.045"82°
    ASME B18.21.11000000000000000
     
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