The Japanese are very finicky about the neatness, cleanliness and appearance of their planes. The YS check valve installed inside the belly pan only functions as a breather for the engine. A check valve is used so no fuel will leak out and there is no need to bore a hole in the belly pan. Refuelling is done thru the line outside with the L fittings and the overflow is thru another line connected to the check valve line with a T fitting and sealed with a fuel dot. Hope I am making sense to you guys. This is the fuel system setup I am using on my Astral XX and my Genesis. By the way, the Nishioka pipe mounts and and one touch belly pan mounts work terrific and are just so convenient.

Jayjay