What is the layer under the car floor mat called?

[MariaLynn]

The layer under the car floor mat is called the floor liner. Maintaining interior cleanliness: The function of car floor mats is roughly the same as that of household floor mats, which can keep the car floor clean. Comfort: The comfort of car floor mats is reflected in two aspects: one is providing certain heat insulation, and the other is shock absorption. Whether for front-engine or rear-engine cars, car floor mats can somewhat reduce the heat generated by the engine. They also absorb a significant amount of vibration from the vehicle's movement on the road. Sound insulation: Car floor mats have certain sound insulation effects. Noise from the car floor will pass through the floor mats before entering the cabin, and these noises will be absorbed and weakened by the mats, achieving sound insulation.