The surface of the heater pad during installation

Fig 1: Bubbles And Kinks Increase Risk Of Damage To Pad

Courtesy of VOLVO CARS OF NORTH AMERICA.

CAUTION:

There must not be any bubbles or kinks when the heater pad is bonded to the foam filling.

Bubbles and kinks increase the risk of damage to the pad during use
NOTE:
This applies to the entire surface, but to the heating wires in particular.