... siphon Fill valve(inlet valve)♥ 1) Anti-siphon fill valve, pressure stopping design..2) Unique design, not sensitive to water quality (polluted water)..3) ... Compacted design fill valve, small bulk, saving space...4) ... short ones).5) Anti-siphon, keeping water from flowing back to inlet pipe..6) Anti-corrosion, long lifespan ensured ...