New, genuine Mazda water hose from rear of head to oil cooler, MX5 1.8 mk2 & mk2.5 1998-2005. Hose, oil cooler inlet, MX-5 1.8 mk2 & mk2.5, BP4W15536A. This runs from the housing on the rear of the cylinder head to the oil cooler (on the filter housing).
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