The evolution of a species – meet the Isotherm Jacket. Lightweight, warm and breathable, we paired an abrasion-resistant Pertex Quantum fabric with Marmot’s super breathable mesh lining and stuffed it with the new state-of-the-art Polartec® Alpha® insulation – a durable woven material that cuts the need for down-proof fabrics. The result is a jacket perfect for a wide range of comfort during active use: a backcountry skier’s dream come true.
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Polartec® Alpha® is a new state-of-the-art synthetic insulation that banishes the need for impervious down-proof fabrics by offering a rare combination of lightweight warmth and true breathability in a "puffy" style garment.
Polartec® Alpha® is a new concept in synthetic insulation focused on unsurpassed thermo-regulation. Unlike conventional synthetic insulations Polartec® Alpha® is a knit material that offers excellent stability and superior durability without the need for scrims or tightly woven fiber proof lining fabrics.
Its unique knit structure allows for the use of highly breathable lining fabrics which permit body heat and moisture vapor to move through the insulation. This air permeability allows for warm air to move from areas of high concentration to areas of low concentration creating a more even distribution of warmth with-in the garment.
Pertex Quantum® is the lightest down-proof by construction fabric available. It is a true featherweight at around 30g/m2 and uses the finest yarns available with the maximum thread count.
Why do we encourage proper care of our clothing and gear?
Because you have invested in (or are thinking about investing in) one of the most technically advanced pieces of apparel or equipment you'll ever own and we want to make sure you have the information you need to protect and care for your purchase. Proper care assures you will optimize the performance of your Marmot product and maximize its service-life.