Blister lights are used for signaling and/or marking purposes. The blister lights include a housing which is embedded in a traffic area, e.g. a street, an airport runway for taking off and for landing, or the like. It further includes a housing cover by which means the housing embedded in the traffic area can be closed on its upper side, the cover being detachably connected to the housing and including at least one light outlet. It additionally includes an illuminating element which is arranged in the housing and by which the light can radiate through the light outlet of the housing cover. In order to enable the illuminating element to have higher current densities and thus to enable the blister lights to have a higher light output capacity, a thermoconducting bridge is formed between illuminating element and the housing cover. By this, the thermal energy produced by the illuminating element can be conducted to the housing cover From these, the thermal energy is guided to the traffic area via the housing which is embedded therein.