Close Coupled, 4.5litres single flush with delayed action fill valve Product Details Company Name Armitage Shanks Brand Name Contour 21 Model Number S3054, S3654 Maximum Flow Rate 4.5 l/min Maximum Volume 4.5 litres Category WC Suites Available In United Kingdom Efficiency Rating Chart Company name:Armitage Shanks Model:S3054, S3654 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.