What is a basin mixer taps? A basin mixer is basically a type of mixer tap which mixes both your hot and cold liquid feeds to pass out via a single outlet, which is controlled either by a single handle or twin-handle to achieve the desired flow of liquid at a certain temperature. As this is the most common type of mixer taps available in the market, it is therefore imperative to familiarize yourself with the basic functions of such mixer units and select the one that best suits your needs.