With its round mummy-like shape, the MUMMY LINER THERMOLITE PERF from Cocoon is a sleeping bag liner that acts as a radiator.

Offering an extra warm liner thanks to its Cocoon Thermolite EcoMade Performer fabric, this model adds degrees of cold resistance to the temperature index of the sleeping bag. It's soft and warm, and has great stretch. That's why it has no side openings or clear closures.

This way, the heat is kept to a maximum inside.