Holley EFI Pro Dash Standalone Service Harness

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Your satisfaction is important to us. If you wish to return an item or request a refund, please review the terms and conditions outlined in our Returns Policy.

• Off‑Road Use Only
  Products sold by JS Speed are intended for off‑road use and may be illegal on public roads where emissions or pollution‑control laws apply.
• Check Local Laws
  Before purchasing or installing, verify all applicable local, state/provincial, and federal regulations to ensure the modification is legal in your area.
• Professional Installation Recommended
  These parts should be installed by qualified professional mechanics. Improper installation can cause performance issues or vehicle damage. Unless a product page explicitly states otherwise, installation instructions are not included. Components are designed for users with solid mechanical knowledge, and minor adjustments or modifications may be required for proper fitment. Returns or refunds cannot be accepted due to difficulty completing an installation or the absence of instructions.
• Warranty Impact
  Use of these parts may void your vehicle’s factory warranty. Confirm with your vehicle manufacturer before purchase and installation.
• Limitation of Liability
  JS Speed is not responsible for damage, failures, or issues arising from the use or installation of these products.
• Product Images
  Images are for illustration only and may differ from the actual product due to manufacturer updates or improvements.
• No Performance Guarantees
  While these products are designed to enhance performance, JS Speed does not guarantee specific performance results.