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ARP 400-8321 Stainless Steel Nut - 12-Point Kit 5/16-24

Part of: ARP Stainless Steel Nut

Other options in this family: ARP AMN122 ARP AUN122 ARP 400-8331 ARP 300-8302 ARP 301-8314

Manufacturer

Picture for manufacturer ARP

Part Number

400-8321
16 reviews
Sale Price

$6.61

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The ARP 400-8321 is a pair of high-performance 12-point nuts manufactured from aerospace-quality ARP 300 Series stainless steel. Engineered for performance and racing applications, these premium fasteners deliver exceptional strength and corrosion resistance for engine builds, intake manifolds, headers, and other critical automotive applications.

Key Features:

  • Thread Size: 5/16-24
  • 12-point design for superior grip and ease of installation in tight spaces
  • Manufactured from ARP 300 Series stainless steel for maximum corrosion resistance
  • 180,000 psi tensile strength rating
  • 3/8-inch socket size for easy wrenching
  • Polished finish for professional appearance
  • Sold as a pair (2 pieces)

ARP (Automotive Racing Products) has been the gold standard in performance fasteners since 1968, trusted by professional builders and racers in Formula 1, IndyCar, NASCAR, and NHRA applications. These stainless steel nuts provide superior strength compared to Grade 8 hardware while maintaining excellent resistance to rust and corrosion, making them ideal for marine, street, and race engine applications.

quick and easy. now the waiting game

Wish I had a number to talk directly w seller

Correct bulkhead kit for the top nut that starting splitting in half.

able to find old parts for a reasonable price with fast shipping

I had never ordered off Autoplicity but I'm very happy I did crazy fast delivery time and great service overall, very pleased and will shop with again!

Great

Quick simple and easy. Had no issues with this order so far

Great price!

all about the price, nice! perfect fit, very smooth purchase.

Great Price! Fast shipping!!!

Great service. Quick shipping!

Everything went smoothly and my order arrived in a reasonable amount of time.

I have had good experiences so far with Autoplicity.

easy to use site, quick and easy, cant wait to get item. Coupon was a huge plus

Great prices

Payment with Amazon is great!!

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