How Thermal Mass Changes the Behavior of a Kapton Heater
https://modern-heating-elements.greyhavendaily.com/posts/ito-glass-heater-vs-conventional-heating-elements-key-differences
In precision instruments, a kapton heater must deliver heat in a controlled way. It uses a resistive foil circuit laminated within polyimide film. One useful trait is custom circuit patterns. Still, hot spots can change the result