The Reactor Midweight enhances your sleep system with advanced Thermolite® Pro fabric. Infrared-absorbing ceramic pigments and hollow-core fibres trap body heat, adding up to 6°C|11°F to a sleep system with minimal bulk. Stretch-knit fabric and arm openings allow unrestricted sleep, making it a great fit for any shape sleeping bag. Quick-drying and easy to clean, it features HeiQ Fresh odour control and helps extend your sleeping bag’s lifespan by reducing wash frequency.