The thermal liner provides a majority of the thermal protection from the ambient heat in the room. The more thermal lining there is, the less heat the firefighter will feel. The less thermal lining there is, the more heat the firefighter will feel. Thermal liners consist of a face cloth and batting. The face cloth can be spun fiber or a blend of spun and filament fibers. The filament adds slickness to the face cloth, which makes it comfortable to wear and work in. The batting can be a one-layer product like a felt, called needlepunch, or multiple layers of spunlace that are made by using water jets to entangle the filaments of the fiber, which is lighter and more flexible.