Insights

How to Choose a Fleece Jacket: The Ultimate Guide

More Than Just a Fleece – A Performance Essential

A fleece jacket isn’t just about warmth; it’s about resilience, adaptability, and performance when it matters most. Whether you're navigating alpine ascents, pushing through sub-zero temperatures, or layering up for an urban mission, choosing the right fleece is critical.

But with so many options available, how do you separate a true technical layer from a casual throw-on? This guide will take you through everything you need to know – from understanding fleece technology to selecting the best one for your needs.

What is fleece?

Fleece is a high-performance synthetic fabric engineered for warmth, breathability, and durability. Unlike wool, it offers superior moisture management, keeping you warm and dry in extreme conditions.

At the pinnacle of fleece technology is Polartec®, the original innovators of synthetic fleece. Their advanced textiles are designed to handle the harshest environments, offering unparalleled insulation while remaining lightweight and breathable. ThruDark utilises Polartec® High Loft™ and Polartec® Thermal Pro™ in our technical layers, ensuring elite performance in demanding conditions.

ThruDark's pick: Heritech Moorland Fleece - Inspired by heritage design, adapted for technical performance.

Fleece comes in three primary weights:

  • Lightweight: Perfect for high-intensity activities or as a layering piece in moderate temperatures (7-15°C).
  • Midweight: Versatile for colder conditions, balancing warmth and breathability for pursuits like skiing and mountaineering.
  • Heavyweight: Maximum insulation for extreme cold, often used as an outer layer in static environments or layered beneath a technical shell for expedition-level protection.

The Science of Warmth

The key to fleece’s insulating power lies in its structure. The synthetic fibres create air pockets that trap body heat, while moisture-wicking properties ensure sweat evaporates, keeping you dry. Polartec® fabrics elevate this further with proprietary weaves and hydrophobic yarns that maximise warmth while minimising weight and bulk.

Explore our full fleece range to see how ThruDark integrates cutting-edge materials into every design.

ThruDark's pick: Mantra Fleece - a mid-layer for extreme cold conditions but is just as reliable when worn as an outer layer.

How Should a Fleece Jacket Fit?

Fit is everything. A poorly fitted fleece won’t perform when it matters most. Here’s what to look for:

1

Snug, but Not Restrictive

A fleece should fit close to the body without restricting movement. Excess material leads to inefficiency, while a tailored fit enhances thermal regulation and layering compatibility.

2

Freedom to move

Technical performance demands a precision-engineered fit. Look for articulated sleeves and gusseted underarms that allow unrestricted movement whether you’re ascending, descending, or reaching for your next hold.

3

Layering Compatibility

A fleece should integrate seamlessly into a layering system. Midweight and heavyweight fleeces should allow space for a base layer beneath while fitting comfortably under a weatherproof shell.

For elite performance, our ThruDark fleece collection is designed with these principles in mind, balancing fit, warmth, and functionality.

Choosing the Right Fleece: Key Considerations

Material & Construction

Not all fleece is created equal. Polartec® fabrics are the benchmark in technical insulation, offering superior durability, stretch, and thermal efficiency.

Polartec® High Loft™ – Maximises warmth-to-weight ratio with increased breathability and packability.

Polartec® Power Grid™ – Engineered for moisture control with grid-patterned channels that enhance breathability and reduce fabric bulk.

ThruDark's pick: Centurion Alpine Jacket - is a versatile, hooded soft-shell designed as a mid-layer for advanced technical pursuits across rugged terrain and hostile conditions.

Warmth vs. Weight

Choosing the right warmth level depends on your activity:

Lightweight Fleece: High breathability for dynamic movement. Best for climbing, trail running, and fast-paced alpine adventures.

Midweight Fleece: A versatile all-rounder, balancing insulation and moisture control. Ideal for skiing, hiking, and deployments.

Heavyweight Fleece: Maximum insulation for extreme cold. Best as an outer layer in static conditions or beneath a shell for full protection.

ThruDark's pick: Mantra Gilet - a versatile mid-layer for mountaineering and other dynamic cold weather pursuits.

Breathability & Moisture Management

Overheating is a performance killer. Polartec®’s advanced moisture-wicking properties pull sweat away from the body, allowing rapid evaporation while maintaining core temperature regulation.

ThruDark's pick: Siege Tech Fleece Hooded - is a lightweight mid-layer, ideal for hiking, mountaineering, skiing and trail running in colder climates.

Durability & Weather Resistance

ThruDark fleeces are built for the extreme, featuring reinforced panels in high-wear areas to withstand rugged terrain. Some fleeces feature DWR (Durable Water Repellent) coatings, adding a layer of weather resistance when conditions turn harsh.

ThruDark's pick: Centurion Alpine Jacket - is a versatile, hooded soft-shell designed as a mid-layer for advanced technical pursuits across rugged terrain and hostile conditions.

FOR ALL YEAR ROUND

SHOP FLEECE JACKETS

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CENTURION ALPINE JACKET

CENTURION ALPINE JACKET

$506 CAD

Essential Features to Look For

The right features can elevate your fleece from good to elite:

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Zippers:

Full-zip for versatility, half-zip for minimal bulk.

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Pockets:

Hand-warmer pockets, chest pockets, and internal compartments for essentials.

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Hood:

Added insulation and protection against the elements.

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Thumb loops:

Keep sleeves secure and provide extra coverage.

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Reinforced Panels:

Extra durability in high-impact areas.

Every detail in ThruDark fleece jackets is designed for ultimate performance and resilience in the field.

Why Choose ThruDark?

Designed and tested by Special Forces veterans, ThruDark’s fleece jackets aren’t just another layer – they’re engineered for resilience in the most demanding conditions. We integrate cutting-edge Polartec® fabrics, meticulous tailoring, and field-proven design to ensure elite performance.

Whether you’re operating in extreme environments or seeking next-level technical apparel, ThruDark fleece jackets set the benchmark.

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