Patagonia's Yvon Chouinard and Malden Mills Company (now, known as Polartec) were the first to develop fleece jackets in Synchilla (as in synthetic chinchilla), to create better insulation for rock climbers and backpackers. Over the years, many brands have created their own versions from casual to high fashion. Slam Jam selects the finest fleece jackets from The North Face, AMOMENTO, Patagonia, and more.