Their only cooling mechanism is panting.
Above around 28°C, that's no longer enough. For short-nosed breeds like Pugs or Frenchies, it's already too much from 20°C. What looks like normal summer behavior is often a warning sign.
And summers keep getting hotter.
Heat days have more than doubled since 1990. What used to be the exception is now the norm from June to September.
Most cooling mats don't solve this.
They leak, can't withstand claws, and end up in the trash after one summer. Fans, wet towels, or early walks help in the short term, but they're not enough.