Insulation.

Polartec® Fleece is the original synthetic fleece and was <a href="https://www.polartec.com/about">invented by Polartec in 1981</a>. Often known as polar fleece, it is a soft knitted fabric designed to trap body warmth while remaining lightweight, breathable, fast drying, and durable. <br> <br> Polartec fleece comes in several weights, including Micro, 100, 200, and 300 series, so you can choose the right level of warmth ranging from lighter fleece layers to heavier options designed for cold weather insulation.

Fleece is a knitted fabric with a raised, fuzzy surface that traps warm air. It is breathable, fast drying, and is often worn as a standalone layer or mid layer for active use and moderately cold conditions. <br> <br> Insulated fabrics are specifically built to retain warmth while managing airflow and packability. <a href="https://www.polartec.com/fabrics/insulation/alpha">Polartec® Alpha™</a>, for example, uses a lofted fiber structure with a mesh core to provide breathable warmth that adapts to changing activity levels and start-stop conditions. <br> <br> Generally speaking, fleece prioritizes soft, steady warmth, while insulated fabric is designed for lighter, more compressible warmth for dynamic situations and changing conditions.

<a href="https://www.polartec.com/fabrics/insulation/fleece-series">Polartec® Fleece</a>, also known as polar fleece, is best used for cold weather layers that combine soft warmth, breathability, and quick drying performance. It is ideally suited for outdoor fleece jackets, mid layers, and standalone pieces designed for hiking, skiing, climbing, and everyday cold weather wear. Beyond outdoor gear, Polartec® Fleece is increasingly used by fashion apparel brands for its soft hand and aesthetic appeal. <br> <br> <a href="https://www.polartec.com/fabrics/insulation/fleece-series">Polartec® Fleece Series</a> comes in multiple weights, including Micro, 100, 200, and 300 series, letting you choose lighter fleece styles for active layering or heavier fleece for more warmth in colder conditions.

For lightweight warmth, <a href="https://www.polartec.com/fabrics/insulation/fleece-series">Polartec® Fleece Micro</a> is the best fit. This microfleece is ultralight and designed for mild conditions or easy layering, delivering warmth without extra bulk. <br> <br> For a slightly warmer lightweight fleece, <a href="https://www.polartec.com/fabrics/insulation/fleece-series">Polartec® Fleece 100</a> offers breathable warmth and works well as a light mid layer. Both are part of the Polartec fleece family and use a raised pile construction to trap warm air efficiently.

Performance fleece is synthetic fleece engineered for warmth, breathability, durability, and active use. Unlike basic fleece, it is designed to meet specific conditions without adding unnecessary bulk. <br> <br> <a href="https://www.polartec.com/fabrics/insulation/thermal-pro">Polartec® Thermal Pro™</a> supports versatile warmth and breathability, while <a href="https://www.polartec.com/fabrics/insulation/wind-pro">Polartec® Wind Pro™</a> adds greater wind resistance and water repellency for variable weather. Both are built to balance comfort, protection, and performance in demanding conditions.

Traditional fleece provides static warmth by trapping air, but it can retain heat and moisture during activity. Performance fleece uses advanced fabric technologies to improve breathability and moisture management, helping helps regulate body temperature and keep you comfortable across a wider range of conditions and activity levels. Some Polartec performance fleece, such as Polartec® Wind Pro™ and Polartec® Wind Pro™ FR even offer wind and fire protection. <a href="https://www.polartec.com/fabrics/insulation/wind-pro">Polartec® Wind Pro™</a> uses a tight knit construction to block more wind than standard fleece while staying warm, breathable, durable, and water repellent. <br> <br> For work environments that also require flame resistant protection, <a href="https://www.polartec.com/fabrics/flame-resistant/wind-pro-flame-resistant">Polartec® Wind Pro™ FR</a> offers similar wind resistant fleece performance with added FR protection.

Lofted fleece helps keep you warm by creating small thermal air pockets within the fabric that trap body heat without adding heavy bulk. <br> <br> The raised pile structure of <a href="https://www.polartec.com/fabrics/insulation/high-loft">Polartec® High Loft™</a> increases warmth while keeping the fabric lightweight, breathable, and compressible. This helps provide strong insulation while still allowing excess heat and moisture to escape during activity.

The best way to reduce fiber loss during washing and long term uses is to choose an insulated fabric with shed reduction technology. <a href="https://www.polartec.com/fabrics/insulation/fleece-series">Polartec® Fleece</a> with Shed Less Technology is expressly designed to reduce fiber shedding over time. <br> <br> <a href="https://www.polartec.com/fabrics/insulation/power-air">Polartec® Power Air™</a> also helps reduce shedding by encapsulating insulating fibers inside a smooth shell, limiting fiber breakage and loss while still providing lightweight, breathable warmth.