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The Mishimoto 42mm Aluminum CNC Coolant Fill Neck is an essential component for custom radiator builds and modifications. Crafted from high-quality CNC-machined aluminum, this large fill neck provides durability and precise fitment for your automotive cooling system. It is designed to be welded onto custom radiators, offering a reliable and professional-grade solution for aftermarket and custom projects. The fill neck features a 42mm diameter, ensuring compatibility with Mishimoto radiator caps, and includes a screw-in overflow nipple for added functionality and ease of use. Whether you're fabricating a new radiator or upgrading an existing one, this aluminum fill neck provides a seamless integration point for coolant filling and overflow management. Its universal fitment and high-quality construction make it an excellent choice for automotive enthusiasts and professional builders alike. The Mishimoto Aluminum Coolant Fill Neck is ready for welding, ensuring a secure and leak-free connection in your custom radiator setup. Built with attention to detail and precision, this part is designed to enhance the durability and performance of your cooling system while maintaining a clean, professional appearance. Trust Mishimoto’s reputation for quality and innovation to meet your custom radiator needs efficiently and reliably.
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).
