ARP 1/4-20 x 0.515 12pt Stainless Steel Bolts
The ARP 611-0515 is the #1 selling 1/4-20 x 0.515 12pt stainless steel bolt set for high-performance applications. Premium 300 series stainless steel construction delivers superior corrosion resistance, exceptional strength, and precise fitment the ultimate bolt upgrade for any engine, chassis, or accessory build requiring reliable fastening under extreme conditions.
Key Features
- 300 Series Stainless Steel – Premium corrosion-resistant material for long-lasting durability
- 12-Point Head Design – Allows higher torque application and better clearance in tight spaces
- 1/4-20 Thread – Standard coarse thread for strong holding power in most applications
- 0.515in Length – Ideal length for specific engine and accessory mounting needs
- Precision Machined – Tight tolerances ensure perfect fit and reliable clamping force
| Spec | Detail |
|---|---|
| Part Number | 611-0515 |
| Brand | ARP |
| Thread Size | 1/4-20 |
| Length | 0.515 in |
| Head Type | 12-Point |
| Material | 300 Series Stainless Steel |
| Country of Origin | United States |
| Warranty | ARP Limited Lifetime Warranty |
Whats Included
- Set of ARP 1/4-20 x 0.515 12pt Stainless Steel Bolts
Product Notes
- Superior corrosion resistance compared to standard steel bolts
- Ideal for engine, chassis, exhaust, or accessory mounting
- 12-point head allows higher torque and better tool access
Installation Notes
- Use proper torque specs to avoid thread damage
- Estimated time: 5–15 minutes per application
- Apply anti-seize if required for future removal
This Part Fits
| Year Range | Make | Model | Trim / Engine | Notes |
|---|---|---|---|---|
| Universal | Universal | Universal | 1/4-20 applications | Engine, chassis, accessory mounting |
Why Choose ARP Stainless Steel Bolts?
- #1 choice for high-performance and race applications
- Built & tested in the United States
- Chosen by engine builders and racers for strength and corrosion resistance
Frequently Asked Questions
-
Q: Are these bolts stronger than Grade 8?
A: Yes, ARP stainless offers superior strength and corrosion resistance. -
Q: Can I use these in high-heat areas?
A: Yes, 300 series stainless excels in exhaust and engine bay applications. -
Q: What torque should I use?
A: Follow ARP torque recommendations or standard 1/4-20 specs for stainless.
Shipping & Handling
- Method: Ground UPS or FedEx
- Availability: In stock – ships same or next business day
- Packaging: Official ARP retail box
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