Abstract: A motorcycle helmet defines a cavity in a hard fiber shell. A thermo-electric heat pump is mounted in the cavity, and a light metal rediator is bonded to both shell and pump. One way conductors energize the heat pump from a motorcycle battery source to pump heat from the hard fiber shell to the radiator. A flexible blatter filled with heat transfer liquid is mounted in the hard fiber shell and below the heat pump and in thermal contact with a wearer's head and the heat pump, for conducting head heat to the pump to electrically pump to the radiator for radiation to the atmosphere.