Designed with streamlined baffles that are contoured to fit your body, our ThermoBall™ powered by PrimaLoft® offers ultralight, highly compressible synthetic insulation to keep you warmer in cold, wet weather.
The North Face™ developed a partnership with PrimaLoft® to offer a new synthetic alternative to down. ThermoBall™ is a revolution in insulation technology. Unlike traditional, continuous-filament synthetic insulations, the small round PrimaLoft® synthetic fiber clusters closely to mimic down clusters; trapping heat within small air pockets to retain warmth.
Independent CLO testing has shown that ThermoBall™ technology can offer the low weight, loft, warmth, and compressibility of down with the wet-weather insulating performance of synthetics.