From Rose's Fabrics & Handmade:
Double Brushed Poly Fabric
Weight 170 GSM
Who wouldn’t want to drape their bodies in this incredibly soft fabric? DBP is a 4-way stretch knit made of 96% polyester/4% spandex. It has also undergone a process where both sides of the fabric are brushed, creating that characteristic suede like feel on both sides.
It has excellent recovery and lovely drape, making DBP an excellent fabric for tops, dresses, skirts, and especially leggings.