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Factor 1 Base

These base layers are manufactured using patterns based on the Meraklon range. They should be worn snugly but not restrictive. Unisex leggings (no Fly) are only produced currently in this range.

Chest Inches 28-31 32-34 35-37 38-40 41-42 43-45
Chest CM 71-79 81-87 89-94 97-102 104-107 109-114
Back drop inches 24 26 28 30 32 33
Back drop cm 61 66 71 76 81 84
waist inches 26-28 29-31 32-34 35-37 38-40 41-42
waist cm 66-71 74-79 81-87 89-94 97-102 104-107
inside leg inches 24 27 28 29 30 31
inside leg cm 61 66 71 76 81 84
womens uk 6 8-10 12 14 16 18
womens european 34 36-38 40 42 44 46

Sub Zero Factor 1 Sports Vest Unisex Base Layers


Sub Zero Factor 1 Sports Vest Unisex Base Layers are manufactured from tubular 100% polyamide fabric that eliminates the need for side seams on standard base layer sizes. If you require petite thermal underwear for women (XS) or plus size thermal underwear (XXL+) then the fabric has to be opened out and cut from different patterns. This means that flat side seams will be present. All of our Factor 1 base layer tops have extra generous body lengths giving you a decent amount of fabric to tuck in to your trousers. This prevents lower back exposure when you bend over to tie your shoe laces or look for something in your backpack.

The shoulders are closed using flat seam stitching which eliminates chaffing when wearing a rucksack. The neck profile is lower than the other Factor 1 thermal tops so they can be worn discretely under work clothing.

Sub Zero Factor 1 sports vest unisex base layers are ideal for adding extra insulation without adding bulk to your arms, making them perfect for rowers and runners. They are also handy to wear under your work clothes or when commuting. Teaming them up with the Sub Zero Factor 2 thermal mid layer underwear range adds extra warmth in extreme conditions.


Made in: England

Sun protection factor: 50+

TOG rating: 0.42

Fabric: 100% Polyamide

Average weight: 115g / 4.1oz

Fit: Unisex snug

Layer: First - next to the skin

Size availability: XSmall-2XLarge

Colours: Black, White

Fabric treatments: Hydrophilic impregnated

Washing instructions: 40°C wash with mild detergent, do not tumble dry, iron on low setting


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