WC BACK TO WALL. Product Details Company Name Hidra Ceramica SRL Brand Name DIAL Model Number DL10 Maximum Flow Rate 4.5 l/min Maximum Volume 4.5 litres Category WC Suites Available In United Kingdom Efficiency Rating Chart Company name:Hidra Ceramica SRL Model:DL10 4.5 l/min The average flushing volume for dual flush WC Suites and Cisterns is calculated as (a + (3 × b)) ÷ 4, where a is the full flush value and b is the low flush value.