Buy the highest quality breathable, calendered ripstop/taffeta nylon and polyester fabrics in several different weights/varieties at Rip Stop By The Roll. Calendering is a finishing process that is used on ripstop nylon fabrics where the fabric is passed under rollers at a high temperature and pressure. This calendering process fuses the individual nylon yards together and makes the nylon fabric resistant to down and other fine filaments from poking through the fabric. All of the fabrics below are DOWNPROOF and suitable for use with down gear. Our ROBIC, Ripstop, HyperD, and MEMBRANE poly taffeta nylon fabrics are great for projects such as top quilts, underquilts, hammocks, sleeping bags, jackets, and pillows.