to the lens to be hot enough to keep snow and ice build up from occurring key features of our heating implementation are the simplicity of having a heater and thermostat all in one unit and also the power tie in before the voltage regulator circuit in the existing light hardware i e a vehicle 12 vdc source a new feature is the upgraded heat sink 24 and 26 used with the ptc element 14 and 16 which allows for maximum radiant heat to be achieved when constructing these units each heat sink 24 and 26 is pried open along a medial section and a respective ptc element 14 and 16 is inserted therein after which the medial segment of the heat sink is physically compressed onto the respective ptc element 14 and 16 and silver solder is applied therebetween to affix the element and provide a heat transfer pathway that will also withstand the rapid heat change and also provide for a good connection a high heat uv cured adhesive can also be used to keep and retain components secure from vibration and act as a heat barrier to protect the existing circuitry as shown in fig6 9 fig3 provides data for the custom ptc heater of fig1 and 2 and fig4 provides a power curve the present custom designed ptc heater is made to turn on when temperatures are below 32 degrees fahrenheit and to keep the ambient temperature at.