Viva Sanitary Toilet Cistern Siphon Diaphragm Washer For AS01 SKU : 100433 Toilet Cistern Siphon Washer Replacement] Holes as shown Dimensions of the overall washer are 130mm x 78mm Center hole is 12mm diameter Offset holes are 1mm diameter If your syphon is not flushing as it should and has lost suction replacing this washer should solve it. .
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