The novel device is directed towards a Preferential Liquid Line Mechanical Switchover device which comprises of main housing, multiple inlets, at least one out-let wherein a transparent indicator. This device allows to get the preferred liquid from the outlet, for an example – at home, first preference is to get the water at out let either from fresh water supply or from over head tank, however when fresh water supply by authority is coming the preference would be given to fresh water instead of water from over head tank. This device is capable of automatic switchover from over head water line to fresh water line, when fresh water is available at the inlet.