Fire Sleeve 4AN 12mm ID 9ft Black

The Fire Sleeve 4AN 12mm ID 9ft Black from REDHORSE PERFORMANCE is a high-temperature braided hose sleeve engineered for fuel, coolant, and fluid line protection in modern performance builds. As a mechanic working with turbocharged and supercharged platforms, you'll recognize this as essential infrastructure for any serious engine modification—especially when routing fuel or coolant lines near exhaust components, headers, or turbo manifolds. Fire sleeves prevent heat degradation of hose jackets and reduce the risk of fluid loss due to thermal breakdown in underhood environments where temperatures exceed standard cooling capacity.

This sleeve features a 12mm inner diameter (ID) construction, compatible with standard 4AN hose fittings—the metric equivalent to -4 SAE hose sizing. The nine-foot length provides substantial coverage for long fuel or coolant runs from engine bay to tank, fuel cell, or remote cooler installations without requiring multiple splices. Black braided nylon exterior reflects heat and blends seamlessly into engine bay aesthetics while the interior ceramic or silicone-impregnated lining insulates against radiant and contact heat sources. The 4AN sizing handles moderate flow rates typical of EFI fuel systems and auxiliary cooling circuits, making it ideal for street performance and track-duty applications where thermal management determines reliability.

Technicians upgrading forced-induction systems, installing aftermarket fuel delivery, or reconfiguring coolant paths will benefit from this proven REDHORSE solution. The 9-foot length accommodates custom engine bay layouts without waste, and the fire sleeve's snug 12mm ID fit over 4AN hose reduces vibration chafing—a common failure point in high-rpm builds. Installation requires no special tools; simply slide the sleeve over your hose before final fitting, and secure with cable ties or hose clamps at intervals. Compatible with both -4 AN and metric 4AN hose assemblies, this sleeve meets DOT standards for performance fuel systems and cooling circuits operating at elevated temperatures.