The Heating Port on our injectors is for a soldering iron to heat your injector which in turn heats your resin during a repair. Warm resin will wet and wick the glass better. Cold resin will not flow, wet or wick the glass which will compromise your adhesion to the glass. So weather (sic) your mobile or in a shop during the cold months heat your resin for a better repair that will also drop the viscosity, increase flow and decrease your repair time.