Marine Fuel Line Hose - MRF
These are specifically designed and branded for use in supplying fuel to motors in boats or marine vessels. USCG Type A1 hoses are designed for fuel feed applications where the fuel is constantly in the hose, whereas Type A2 hoses are designed for fuel fill type hoses only. The "A" refers to meeting flamability tests and the "1 or 2" differentiates the hoses for fuel permeability tests - "1" being suitable for constant fuel contact where as "2" would not meet constant fuel permeability tests.