Polartec and Kraig Biocraft Laboratories are planning to bring the first fabrics made from spider silk to the performance apparel market. The two companies, in joint development since 2016, are currently using the performance features of spider silk in yarns for military-grade textiles. Kraig, a biotechnology company focused on the development and commercialization of spider silk, possesses the exclusive right to use patented spider silk gene sequences in silkworms. This is a way to mass produce these fibers responsibly. Spiders cannot be raised in colonies, and in order to make silk, competitors rely on genetically engineered E.coli bacteria, which produce high levels of carbon dioxide, the companies explained. Spider silks are thin, flexible and strong, in addition to being fully renewable, biodegradable and biocompatible. Their physical properties are expected to enable production of apparel with breathable comfort and excellent durability.