NEMO footprints are 68-75D abrasion-resistant nylon or polyester tarps that are perfectly sized to fit underneath the corresponding NEMO tent. Adding this layer of durable, waterproof fabric reduces wear and tear on your tent floor, which can be caused by camping on rough or rocky ground. Features:- Footprints are sized to perfectly fit their corresponding NEMO tent. 68-75D waterproof nylon or polyester (specs vary by model). Abrasion-resistant material helps protect and extend the lifespan of your tent floor. Sized to fit underneath tent without being visible. Protected by the NEMO Lifetime Warranty.