VorTex fabric is composed of high micro-fiber thread count constructed Polyester for a luxuriously smooth surface. The tight knit structure with the addition of DWR (Durable Water Resistance) are key in making this fabric wind and water resistant as well as light weight and durable. Water will immediately bead and roll off the fabric. This material has great wicking properties and is fast drying. At only 68 GSM or 2 OSY., this garment will fold down to virtually nothing providing great stowability.