Petzl Absorbent Foam One Size. It absorbs perspiration and is machine washable. It is compatible with all Petzl helmets. Specifications for Petzl Absorbent Foam: Manufacturer: Petzl Size: One Size Weight: 10 g Fabric/Material: Polyethylene Features of Petzl Absorbent Foam Open-cell foam absorbs perspiration Machine washable Compatible with all Petzl helmets Package Contents: Petzl Absorbent Foam Petzl A042MA00: Absorbent Foam One Size