SKU: AERFCM3727
UPC: 678146008633
MPN: FCM3727
The AEROQUIP #12 O-Ring Boss Plug (FCM3727) is a precision aluminum hydraulic adapter designed for high-pressure fluid systems in automotive performance and industrial applications. This compact fitting effectively seals off unused O-ring boss ports, making it ideal for those building custom fuel systems, upgrading brake lines, or fabricating power steering modifications.
Constructed from lightweight aluminum, the #12 O-Ring Boss Plug features a hex-head design for easy wrench access and includes a sealing O-ring that accommodates the standard JIC 37° flare geometry used across automotive hydraulic systems. The aluminum construction ensures minimal weight while providing resistance to corrosion, and the machined finish helps the O-ring seat properly against the boss port.
Fabricators and engine builders installing custom fuel rails, transmission cooler lines, or brake system upgrades will find this plug indispensable for blocking unused ports on manifold blocks or adapter plates. It installs quickly with standard hand or wrench tools and is suitable for any system running SAE #12 boss geometry, including aftermarket fuel injection systems.
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