Geberit Duofix 1120mm WC Frame With Sigma 120mm Concealed CisternDesigned to last, Geberit Sigma frames incorporate tried and tested materials which will serve you for years to come. Installed 60 million times over the past 50 years, Geberit concealed cisterns and flush plates represent the ultimate tried and tested solution. Every blow moulded cistern is factory made leak tested, therefore there are no unnecessary sealings or leakage of the cistern for maximum operational reliability. This dual flush cisterm comes