Dudley Turbo S1-11 diaphragm washer

Dudley Diaphragm Polythene Syphon Washer for turbo S1-11

Fits all S1 - S11 syphons (usually green and white).    

Approximate size of diaphragm 147mm x 91cm

If your toilet isn't flushing very well or requires several flushes to clear then the first and cheapest part to chance to try and resolve the problem is the diaphragm inside the syphon.   The old diaphragm will have shrunk in size overtime, cracked and even distinegrated.   Replacing it could resolve the issue.