Generally, synthetics are vied as a substitute for down, which, despite having a lower weight-to-warmth ratio, is not susceptible to moisture. As a result, different fillings are used for the same sleeping bag structures. Indeed, one of the strengths of synthetics is resistance to moisture. However, we wanted to benefit from pros of fillings we use in our products. That is why we used two synthetic fillings. Climashield with a sheet like structure ensuring stability, durability and great freedom of design. Featherless, which mimics the structure of down and provides the best weight to warmth ratio among synthetic insulators on the market.