Men's Fleeces & Mid Layers

A men's mid layer sits between your base layer and outer shell. It insulates, manages moisture, and regulates temperature as conditions change. Types include:

• Men's fleece jacket: providing warmth-to-weight and breathability for hiking, skiing and mountaineering our Siege Tech Fleece is packable and breathable.
• Men's fleece vest: our Mantra Fleece Gilet packs insulation around the body's core without restricting arm movement.
• Men's fleece quarter zip: compact, our Mantra Fleece can be pulled on for temperature control in variable conditions.
• Insulated mid layer: higher warmth-to-weight for cold, lower-output environments, our Bastion Jacket can be worn under a waterproof hard shell in extreme cold, wet conditions.
• Hybrid mid layer: These feature mixed construction, as in our Mountain Pro Fusion Jacket, such as fleece and insulation for balancing high-output pursuits across changing conditions like alpine climbing.

Provided you're moving, one mid layer should usally be enough to keep you comfortable. In extreme cold, if you're remaining static, you may wish to add a further layer accordingly.

You might consider something like our Siege Tech Fleece as a core mid layer, a great all rounder that breathes well and retains a high level of insulation. It's also made from a thinner Polartec Power Grid fabric which gives you more room for maneouvre under a hard shell or insulated jacket. Should you then need to add further insulation, consider a Mantra Fleece Gilet that will provide additional insulation around the core without compromising range of movement.It's essential that if you are adding layers these stay removable during high output, and fit cleanly under your outer shell without bunching.

A men's ski mid layer must handle the full range from a hard run to a cold chairlift. Key attributes:

Insulation-to-weight: warmth without bulk inside a ski jacket.

• Breathability: vents heat efficiently during effort.
• Moisture management: wicks sweat before it chills against the skin.
• Shell compatibility: close fit, no bunching at the shoulders or torso.
• Temperature regulation: transitions between high and low output without removal.

A men's hiking mid layer must perform across variable exertion and shifting weather throughout the day, we've tested our range on Alpine slopes, the Welsh hills and even the infamous Snowman Trek of Bhutan. The key attributes for a good hiking mid layer are:

• Breathability: the primary consideration for challenging ascents, the Polartec High Loft fabric on our Phalanx Fleece is knitted specifically to enhance airflow whilst on the move.
• Moisture-wicking: moves sweat from the skin before it chills, our Centurion Jacket is constructed from Polartec Power Air that helps keep moisture moving as you do.
• Lightweight warmth: every gram matters as distance and elevation increases, opt for our Wraith range of Polartec Alpha mid layers for insulation that packs a punch at a low carry weight.
• Packability: our light Siege Tech Fleece compresses easily into a backpack when conditions change.

Men's fleece jackets function as mid layers in a three-layer system: base layer for moisture management, fleece for insulation, and waterproof shell or insulated jacket for weather protection. Pair lightweight fleeces with merino or synthetic base layers for active pursuits. Midweight fleeces work over thermal base layers in cold conditions. Add a hardshell jacket when weather requires wind or rain protection.

Fleece and wool deliver comparable warmth at similar weights, but perform differently in active use. Fleece dries faster, wicks moisture more efficiently during high output, and maintains loft when damp. Wool regulates temperature across wider conditions, resists odour naturally, and provides better wind resistance. Merino wool performs better for multi-day wear and variable activity levels. In a layering system, fleece excels as an active mid layer while wool works better as a base layer.

The warmest fleeces you can buy typically have a high pile (they're thicker). Like our Mantra Fleece which is made from Polartec® Thermal Pro®, these heavyweight fleeces trap more heat and are ideal for when you're stood around in temperatures below 0°C. These fleeces generally prioritise insulation over breathability, which is fine when you're not moving around quite so much.

Men's fleece jackets function best when worn as a mid layer as part of a layering system. Base layers (our Stealth Base Layer makes a great starting point), wick moisture keeping you comfortable, a good fleece keeps you insulated and an insulated jacket (such as our Bastion Insulated Jacket) or waterproof hard shell (like our Aigis Jacket) keeps you protected. You can then remove your fleece as required during high-output efforts if you begin to overheat. In dry, mild conditions you can wear your fleece as an outer layer without the need for insulated jacket or hard shell.

A fleece is a type of mid layer, mid layers can also include lighter insulated jackets and soft shell jackets. Fleeces and insulated jackets both provide insulation, however a fleece (like our Siege Tech Fleece) will usually be more breathable and thus more suitable for milder climates and/or higher paced pursuits. Light insulated jackets, such as our Ithax Jacket or Engage Jacket can be worn beneath a hard shell in extreme conditions. Otherwise, soft shell jackets such as our Veles Jacket are typically worn to provide additional wind and water resistance without the bulk of a hard shell outer layer.

Wash men's fleeces in cold water (30°C maximum) using liquid detergent without fabric softener. Fabric softener clogs fleece fibres and reduces breathability and moisture-wicking performance. Close all zippers before washing to prevent snagging. Air dry or tumble dry on low heat as high heat damages synthetic fibres and reduces loft. Wash fleeces after 3-5 wears to maintain insulation performance. Avoid ironing. Store uncompressed to preserve pile structure and insulating properties.

Our range of Polartec® fleeces makes use of recycled polyester in order to minimise impact whilst improving product lifespan. For example, the Hardface® treatment on our Centurion Alpine Jacket fuses the fleece fabric at a fibre level to prevent fibre shedding with wash and wear. Polartec® Power Air, used on our Mountain Pro Fusion Jacket, is designed specifically to combat microplastic pollution by encapsulating the fibres in sealed pockets, reducing fibre loss by up to 5x. Elsewhere, on our Mantra Fleece, we've reinforced typically high areas of wear and tear with polyamide for greater durability. It's through this combination of conscious fabric choice and considered design reinforcements that we improve the sustainability of our fleeces.