US Patent 7835534 Battery charging jobsite lunchbox

A preferred embodiment of portable lunchbox equipment that is particularly useful at construction and other jobsites is disclosed which provides important desirable features and functionality comprising a housing, at least one charger for charging a removable battery pack, an audio unit for producing an audio signal, a heating unit, an insulated compartment, a cooling unit for the compartment, a cord and plug for connecting said apparatus to a source of AC power, and circuitry for selectively applying power to the audio unit, the charger and the heating unit.