Contacted Ideal Standard recently about above and was advised to go to www.fastpart-spares.co.uk They recommended cartridge S8739NU. From the photo it appears that the bottom casing of this cartridge is made from plastic whilst the original ones where all brass. Wonder if anyone has experience of whether the new ones last as long as the original. I always assumed that the original ones were either made in the UK or Germany but guess current ones are made outside Europe, wonder if quality is comparable? Many thanks.