97-107mm Inlet x 4"/110mm Outlet 90deg Flexible WC Connector (Short Length). There is no British Standard for Flexible WC Connectors but McAlpine Connectors comply to German Standard DIN 1389:2000-05 for Flexible WC Connectors. Tested by German Testi ng House LGA, Certificate Number 0120208-02 and other Testing Houses. Tests prove conclusively that there is no build-up of sediment and the product is perfectly fit for purpose