Aeroquip FCM5156 -6AN to -4AN Straight Union Reducer Fitting

The Aeroquip FCM5156 is a straight AN union reducer fitting designed to connect two different-sized AN hose lines in a single inline assembly. It transitions from a -6AN (3/8") female connection to a -4AN (1/4") female connection, making it an essential adapter for custom fuel, oil, and fluid plumbing systems in automotive and racing applications.

Manufactured from lightweight aluminum with a blue anodized finish, the FCM5156 offers excellent corrosion resistance and durability under demanding conditions. The fitting uses the standard AN 919 37° JIC/AN flare seat design for a leak-free, pressure-rated seal on both ends.

Key Features:

• Straight inline union reducer — -6AN to -4AN
• Lightweight aluminum construction with blue anodized finish
• Standard 37° AN/JIC flare seating on both ends
• Exceeds industry fitting tolerances for reliable, leak-free performance
• Retail carded (FCM-prefix) packaging for individual sale
• Universal fit — compatible with any standard AN plumbing system
• Ideal for fuel, oil, brake fluid, and hydraulic line connections

Aeroquip, an Eaton brand, has been a trusted name in performance fluid connectors for over 65 years, supplying hose, fittings, and adapters across industrial, aerospace, and automotive markets. Note: Aeroquip fitting tolerances are engineered to match Aeroquip hose tolerances for optimal system performance.