The Superlite Compact 25S Self Inflating Mat is made from light weight 20D rip-stop fabric with a TPU membrane for an airtight seal The core of this 4 season mat is made up of quality ultra-lightweight vertically drilled 16kg/m sup3 PU foam for lasting performance and full inflation It also has an easy valve which is used to add air through a closed valve for extra firmness It is ideal for people who are looking for a really light weight mat but with no compromises on performance The 25S model is a slightly shorter length in order to offer minimum weight and pack size making it ideal for competitive challengers