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The HKS Rotary Applications M-Series Spark Plugs, part number HKS50003-M525RE, are designed specifically for high-performance rotary engines. Featuring a heat range of 10.5, these spark plugs are engineered to optimize combustion efficiency and enhance engine responsiveness. Constructed with premium materials, they deliver reliable ignition performance under demanding driving conditions.
Each spark plug offers a precise fit and durable construction to withstand high temperatures and aggressive engine tuning. The HKS M-Series plugs are suitable for a variety of rotary engine applications, providing consistent spark delivery and improved fuel combustion. Their design promotes smoother engine operation, better throttle response, and increased power output, making them a preferred choice among enthusiasts and professional tuners.
These spark plugs are compliant with safety standards and are suitable for street and race applications. Easy to install, they integrate seamlessly with existing engine systems, ensuring optimal performance without the need for additional modifications. Trust HKS's reputation for quality and innovation to elevate your rotary engine's performance with these high-quality spark plugs.
Features:
Order Processing
All orders are processed and shipped within 24 hours of purchase (excluding weekends and holidays).
Orders placed after 3:00 PM EST may ship the following business day.
Shipping Methods
Customers select their preferred shipping method and speed at checkout.
Shipping times are determined by the carrier and cannot be guaranteed by us.
Tracking information will be provided once your order has shipped.
Shipping Coverage
If your package arrives damaged, please notify the delivery driver immediately and contact the shipping carrier to file a claim.
You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.
Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.
Eligibility
Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
Items that have been altered, installed, or modified cannot be returned.
Return Process
Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
Once your return is approved, you’ll receive instructions on where to send the product.
Customers are responsible for return shipping costs unless the item was defective or incorrect.
Refunds
Refunds are issued to the original payment method once the returned item has been received and inspected.
Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).
