The invention concerns a conductive pattern sheet for use in a glazing, comprising a substrate, a conductive pattern arranged on the substrate, wherein the conductive pattern comprises first and second busbars arranged at opposing edges of the conductive pattern for connecting a power supply thereto, a plurality of conductive lines each conductive line arranged between the first and second busbars, wherein at least a portion of the plurality of conductive lines is configured to have a transition region wherein a change from a first resistance per unit length (R1) at a first end of the transition region to a second resistance per unit length (R2) at a second end of the transition region occurs over a predetermined length (L) of the transition region wherein a rate of change of resistance per unit length (R1-R2)/L is from 1 to 16,000 ohms per centimetre squared and the substrate is a polymer sheet.