Isotherm Hoody

$225.00  | #73540

In outerwear’s natural selection, our award-winning Isotherm Hoody is evolution at its best. Ideal for active insulation – necessary for ice climbing or backcountry skiing – the state-of-the-art Polartec® Alpha® insulation cuts the need for impervious fabric faces. Rather, we used an abrasion-resistant Pertex Quantum® face and lined the hoody with hyper breathable mesh. Reinforced softshell shoulders, an attached hood and a free-moving fit – it’s a new species of light, warm and breathable.

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Isotherm Hoody


Feature List
20 Denier Pertex Quantum Fabric, Softshell Shoulder Reinforcement, Attached Hood with Peripheral Cord Adjustment, Zip Chest Pocket, Zip Hand Pockets, Elastic Bound Cuffs, Elastic Draw Cord Hem
Main Materials
Pertex Quantum© 100% Nylon Mini Shadow Ripstop 1.0 oz/yd, 86% Polyester, 14% Elastane 4.0 oz/yd
Center Back Length (Base of neck to bottom of hem)
Regular Fit
0lbs 14.4oz (408.2g)
Insulation Material
Polartec® Alpha®


Polartec® Alpha®

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.

What is it?

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.

How does it work?

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.

What are the benefits of this technology?

  • High breathability allows unrestricted movement of moisture vapor
  • Dries 20% faster than conventional synthetic insulations
  • Extremely versatile much more comfortable in a much wider range of activities than conventional synthetic insulated garments.
  • Highly durable knit structure allows the use of highly breathable lining fabric for maximum air permeability.

Pertex Quantum®

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.

Wash & Care

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.

Clothing Care

  • Machine wash cold
  • Wash separately
  • Powdered detergent
  • Gentle cycle
  • No fabric softeners
  • Do not iron
  • Do not bleach
  • Do not dry clean
  • Tumble dry low
  • Close all fasteners