Aeroquip FCM3591 -03 AN Female Tube Nut Steel Natural Finish

The Aeroquip FCM3591 is a -03 AN (3 AN) Female Tube Nut constructed from natural-finish steel, conforming to the AN 818 standard. Designed for use with 3/16-inch tubing, this tube nut provides a secure, leak-free connection when used as part of a complete AN tube fitting assembly in high-performance fuel, oil, and hydraulic line applications.

Key Features:

• AN Size: -03 (3 AN), compatible with 3/16 in. OD tubing
• Material: Steel with natural (uncoated) finish
• Standard: AN 818 Tube Nut specification
• Retail packaged: FC-prefix denotes carded/clam shell retail packaging, sold individually
• Cross-reference: Also cataloged as FBM3591 (bulk-packaged variant)
• Engineered and tested to stringent safety tolerances for reliable, leak-free performance

Important: The tube nut (AN 818) must be used together with the corresponding tube sleeve (AN 819). Do not mix hose and fitting components from different manufacturers, as each brand is built to specific tolerances and mixing brands may compromise performance and void the product warranty.

Aeroquip Performance Products has been a trusted name in racing and high-performance plumbing for decades, delivering fittings that are tested to work together as a complete assembly for a proper, dependable fit.