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ARP Chrome Moly Hardened Washers

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Part Number

25 part numbers · from $2.81
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from $2.81

In Stock (10+)

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Usually delivered within 2 days

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Product Details

ARP Chrome Moly hardened washers are precision-made fastener washers. They are designed for use with high-strength bolts, studs, and nuts in demanding automotive and racing applications. They are also sold as hardened flat washers or chrome moly flat washers. They give a flat, durable bearing surface under the fastener head or nut.

Key Features:

  • Chrome moly steel construction: Made from a high-strength alloy steel that resists deformation and crushing under heavy clamp loads.
  • Hardened for durability: Heat treatment helps the washer hold up under the high torque loads used with performance fasteners.
  • Even load distribution: Spreads clamping force across the mating surface. This helps protect components and keeps preload consistent.
  • Matched to ARP fasteners: Built to pair with ARP bolts, studs, and nuts for engine, driveline, suspension, and chassis assemblies.
  • Quality control: ARP manufactures its fasteners in the USA and holds them to strict quality standards.

Choose the washer that matches your fastener and application from the available options. ARP is known for its racing-proven fasteners, and these washers are a dependable way to finish a high-performance installation.

Select yours to see vehicle-specific options.

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25 items

Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)7/16 / 13/16
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.438 in.
Washer Inside Diameter (mm)11.125 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.813 in.
Washer Outside Diameter (mm)20.650 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$9.22
PART NUMBER: 200-8530
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)10mm / 0.85
Thickness.120?
Washer FinishBlack oxide
Washer Inside Diameter (in)0.394 in.
Washer Inside Diameter (mm)10.007 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.850 in.
Washer Outside Diameter (mm)21.590 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$10.20
PART NUMBER: 200-8592
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)3/8 / 5/8
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.625 in.
Washer Outside Diameter (mm)15.875 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$8.86
PART NUMBER: 200-8554
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)3/8 / 7/8
Thickness.150in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.875 in.
Washer Outside Diameter (mm)22.225 mm
Washer Thickness (in)0.150 in.
Washer Thickness (mm)3.810 mm
$12.05
PART NUMBER: 200-8688
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold individually.
Size (ID/OD)3/8 / 3/4
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.750 in.
Washer Outside Diameter (mm)19.050 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$2.81
PART NUMBER: 200-8507
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)3/8 / 0.675
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.675 in.
Washer Outside Diameter (mm)17.145 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$8.64
PART NUMBER: 200-8556
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)10mm / 3/4
Thickness.120?
Washer FinishBlack oxide
Washer Inside Diameter (in)0.394 in.
Washer Inside Diameter (mm)10.007 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.750 in.
Washer Outside Diameter (mm)19.050 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$10.20
PART NUMBER: 200-8689
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)7/16 / .995
Washer FinishBlack oxide
Washer Inside Diameter (in)0.438 in.
Washer Inside Diameter (mm)11.125 mm
Washer MaterialChromoly
Washer Outside Diameter (in)0.995 in.
Washer Outside Diameter (mm)25.273 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$8.86
PART NUMBER: 200-8748
In Stock (10+)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a pair.
Size (ID/OD)7/16 / 13/16
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.813 in.
Washer Outside Diameter (mm)20.650 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$3.50
PART NUMBER: 200-8520
In Stock (10)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a pair.
Size (ID/OD)3/8 / 5/8
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.375 in.
Washer Inside Diameter (mm)9.525 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.625 in.
Washer Outside Diameter (mm)15.875 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$3.45
PART NUMBER: 200-8544
In Stock (8)
Usually delivered within 2 days
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)7/16 / 7/8
$8.86
PART NUMBER: 200-8747
In Stock (7)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferYes
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)12mm / .875
ThicknessTBA
Washer FinishBlack oxide
Washer Inside Diameter (in)0.473 in.
Washer Inside Diameter (mm)12.014 mm
Washer MaterialChromoly
Washer Outside Diameter (in)0.875 in.
Washer Outside Diameter (mm)22.225 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$10.20
PART NUMBER: 200-8551
In Stock (5)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)9/16 / 1.00
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.563 in.
Washer Inside Diameter (mm)14.300 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)1.000 in.
Washer Outside Diameter (mm)25.400 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$9.56
PART NUMBER: 200-8535
In Stock (5)
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)5/16 / 0.550
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.313 in.
Washer Inside Diameter (mm)7.950 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.550 in.
Washer Outside Diameter (mm)13.970 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$9.96
PART NUMBER: 200-8584
3 left at this price
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)0.471 / 1.30
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.473 in.
Washer Inside Diameter (mm)12.014 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)1.300 in.
Washer Outside Diameter (mm)33mm mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3mm mm
$19.73
PART NUMBER: 200-8449
2 left at this price
Usually delivered within 2 days
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)10mm / 0.850
ThicknessTBA
$9.93
PART NUMBER: 200-8730
2 left at this price
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a pair.
Size (ID/OD)1/2 / 7/8
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.500 in.
Washer Inside Diameter (mm)12.700 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.875 in.
Washer Outside Diameter (mm)22.225 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$3.53
PART NUMBER: 200-8524
2 left at this price
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
MaterialBlack Oxide
QuantitySold as a set of 10.
Size (ID/OD)5/16 / 13/16
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.313 in.
Washer Inside Diameter (mm)7.950 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.812 in.
Washer Outside Diameter (mm)20.625 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$9.22
PART NUMBER: 200-8588
1 left at this price
Usually delivered within 2 days
Description
Specifications
HardenedYes
Inside Diameter ChamferNo
QuantitySold as a set of 10.
Size (ID/OD)10mm / 0.75
Thickness.120?
Washer FinishNatural
Washer Inside Diameter (in)0.394 in.
Washer Inside Diameter (mm)10.007 mm
Washer MaterialStainless steel
Washer Outside Diameter (in)0.750 in.
Washer Outside Diameter (mm)19.050 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$11.73
PART NUMBER: 400-8544
Ships from manufacturer
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)10mm / 0.850
ThicknessTBA
$3.63
PART NUMBER: 200-8720
Ships from manufacturer
Description
Specifications
HardenedYes
Inside Diameter ChamferYes
MaterialBlack Oxide
QuantitySold as a pair.
Size (ID/OD)5/16 / 0.550
Thickness.120in
Washer FinishBlack oxide
Washer Inside Diameter (in)0.313 in.
Washer Inside Diameter (mm)7.950 mm
Washer MaterialChromemoly
Washer Outside Diameter (in)0.550 in.
Washer Outside Diameter (mm)13.970 mm
Washer Thickness (in)0.120 in.
Washer Thickness (mm)3.048 mm
$3.55
PART NUMBER: 200-8579
Ships from manufacturer
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)5/16 / 0.550
Thickness.120in
$3.55
PART NUMBER: 200-8578
Ships from manufacturer
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)1/4 / .440
ThicknessTBA
$3.40
PART NUMBER: 200-8430
Ships from manufacturer
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)7/16 / .750
ThicknessTBA
$3.53
PART NUMBER: 200-8542
Ships from manufacturer
Description
Specifications
MaterialBlack Oxide
Size (ID/OD)3/8 / 3/4
Thickness.120in
$3.49
PART NUMBER: 200-8677
Ships from manufacturer
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Well I had a discount code that I tried using and it "accepted" it "it said" but it didn't deduct anything from the order total..

Only problem is that loading a cart page keeps changing shipping to 2-Day.

I'm very pleased with the shopping experience. Everything went smoothly and quickly.

From a purely online ordering experience, perfect.

Pricing was clear as described.

Nice

used on line, placed order allwent well

VERY EASY NICE STAFF

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