Climashield® APEX is a synthetic insulation laid as one continuous sheet rather than in separate pieces. UATAC winter jackets use it in two weights: 100 gsm for movement and 136 gsm for static work in hard frost. Some models add a membrane.
The problem cheap insulation creates
A jacket keeps you warm through the first winter and is noticeably worse by the second. The fabric is not the reason: short-staple fill gradually migrates inside the baffles. Cold spots appear across the back and shoulders, loft becomes uneven, and no amount of washing brings it back.
The second familiar story is a jacket quilted every few centimetres «so the fill does not shift». Every stitch line is a hole straight through the insulation, which means a cold bridge. The more quilting, the more of them.
How APEX is built
APEX is made from continuous filament and laid as a single sheet. It does not break into fragments, does not migrate, and therefore needs far less quilting — the jacket can be built with a minimum of through-stitching.
The second practical property is how it behaves when damp. Synthetic insulation keeps insulating wet and dries faster, while down clumps together and loses most of its ability to hold heat. For service where clothing is damp from sweat and condensation most of the time, that is the decisive argument.
Which weight to choose
| Weight | Duty mode | When it fits | Risk |
|---|---|---|---|
| 100 gsm | Movement, work, active tasks | Moderate frost | May fall short in long static work |
| 136 gsm | Position, vehicle, guard duty, observation | Hard frost | Overheating and sweat on the move |
If your duty cycle is mixed, 100 gsm plus a fleece underneath is more practical than one maximum-warmth jacket. Layers can be adjusted; a single fill cannot. Membrane versions also hold wind and water, and in a wet winter that often delivers more warmth than extra grams of insulation.
Why an APEX jacket does not collapse after washing
Continuous filament holds its structure, so the garment recovers its loft after a wash. That matters for clothing you wash often: a budget jacket loses thickness within a few cycles.
One condition: follow the care instructions. Gentle wash, no softener, dry at room temperature. Overheating deforms insulation permanently.
Common mistakes
- Buying the warmest option without considering the duty mode.
- Comparing weights across different insulations as if they were equivalent: 100 gsm of APEX and 100 gsm of cheap wadding are not the same thing.
- Storing the jacket compressed in a stuff sack for months.
- Drying next to a stove or on a radiator.
- Expecting the jacket to replace a base layer and a fleece.
What insulation does not do
Insulation does not generate heat; it only retains what your body produces. If you are soaked with sweat or standing still for hours without food and movement, no weight of fill will save you.
APEX is not water protection either — that is the job of the outer fabric, its finish or a membrane. And it does not hide you from thermal imaging: a well-insulated garment actually sharpens the contrast between covered body and exposed skin.
Selection checklist
- Define the mode: movement or static. That is the choice between 100 and 136 gsm.
- Define the climate: dry frost or wet winter. That is the choice on the membrane.
- Check that the jacket has venting to dump heat without undressing.
- Plan the system: base layer and fleece underneath.
- Size with room for the mid layer.
Frequently asked questions
What is Climashield APEX?
A continuous-filament synthetic insulation laid as one sheet. It does not clump, does not migrate and needs far less quilting, which means fewer cold bridges.
Should I choose 100 or 136 gsm?
100 gsm for active movement and moderate frost; 136 gsm for static tasks on a position, in a vehicle or on guard duty.
Does APEX insulate when wet?
Yes, and that is its main advantage over down: it keeps its structure when damp and dries faster, while wet down clumps and stops insulating.
Can a jacket with APEX be washed?
Yes, on a gentle cycle without fabric softener, dried at room temperature. The filament restores loft after washing, but overheating deforms it permanently.
Do I still need a membrane if the jacket has APEX?
They do different jobs: APEX insulates, a membrane blocks wind and water. In a wet winter the membrane version is often the more practical choice.
Author: Serhii Vynnyk, founder and CEO of UATAC. Updated: 16 September 2026.