Factor 1 Short Sleeve Base Layer Top

Factor 1 Unisex Short Sleeve Base Layer Tops are the perfect choice for those seeking lightweight, high-performance thermal underwear for active outdoor adventures.

Made from 100% polyamide ribbed fabric with advanced hydrophilic treatment, this base layer is designed to wick moisture away from your skin, keeping you dry and comfortable in all conditions. Its stretchy tubular construction offers a snug, flexible fit that moves with you, while the set-in sleeves ensure comfort around the shoulders and armpits.

With a generous body length, this top stays securely tucked in, preventing exposure around the lower back. Ideal for a wide range of activities—from hiking and skiing to camping—this versatile short sleeve top provides the perfect balance of comfort, warmth, and moisture control.

Whether worn on its own in milder weather or layered with other Sub Zero Mid Layer Thermals in colder conditions, the Factor 1 Short Sleeve Base Layer Top is a reliable and durable addition to your outdoor wardrobe.

Please note: These are end of line garments. There may be some slight colour variations where they have been folded, and some may have different versions of our logo, but apart from this these base layers are perfect. We have greatly reduced the price to reflect this.

Scroll down the page for further product details, technical information, sizing, shipping and any washing instructions.

Size
Color

£19.99

Only 1 left in stock.
  • American Express
  • Apple Pay
  • Diners Club
  • Discover
  • Google Pay
  • Klarna
  • Maestro
  • Mastercard
  • PayPal
  • Shop Pay
  • Union Pay
  • Visa
  • Thermal Efficiency: Advanced polyamide Factor 1 fabric construction retains heat whilst wicking away moisture.
  • Lightweight & Breathable: Ensures unrestricted movement and optimal temperature regulation.
  • High Wicking: hydrophilic treatment within the yarn actively transports moisture away from the skin.
  • Set-In Sleeves: Maximises wicking and provides a superior fit.
  • Generous Length: Helps prevent lower back exposure during activities.
  • Unisex Design: Tailored for both men and women for versatile wear.
  • Flatlock Seams: Minimises chafing and enhances comfort during extended use.
  • Easy Care: Machine washable and quick drying.
  • Brand: Sub Zero
  • SKU: SZF1SS
  • TOG: 0.42
  • Fabric: 100% Polyamide
  • Average weight: 140g / 4.9oz
  • Fit: Snug
  • Layer: First - next to the skin
  • Size availability: XSmall-XLarge
  • Colour: Khaki, Black, White, Pine Green
  • Fabric treatments: Hydrophilic
  • Washing instructions: 40°C wash with mild detergent, do not tumble dry, iron on low setting
  • Made in: Great Britain

 

We ship worldwide using Royal Mail, UPS & DPD. Please use the tables below as a guide for working out the shipping prices to your address. Please be aware that the product weights stated in the listings are for the products themselves, not the final weight when packaging is included. Our system will automatically calculate this and provide a total order weight during checkout. 

If you are unable to complete the checkout process when coming to choose a shipping option, then your order may be over the shipping weight limit for your address. Please call us on +44 (0)116 2402634 or email us at sales@subzero.co.uk and we can give you a custom shipping quote. 

For more detailed information regarding our shipping process please visit our comprehensive Shipping Page

UNITED KINGDOM

*All UK orders over £50 are shipped free of charge

Order Weight Royal Mail Tracked 24 Royal Mail Tracked 48 Royal Mail Guaranteed Before 1pm DPD Next Day
0.5kg £5.49 £3.99 £9.99 £8.99
1.0kg £6.49 £4.99 £11.99 £8.99
1.5kg £6.49 £4.99 £13.99 £8.99
2.0kg £6.49 £4.99 £13.99 £8.99
10.0kg N/A N/A N/A £8.99

 

* Royal Mail guaranteed service and DPD next day service is not available for Jersey, Guernsey, Isle of Man and Northern Ireland.

USA & CANADA

*All USA & Canada orders over £200 are shipped free of charge

Order Weight DPD 7-14 Days Royal Mail International Tracked
0.25kg £16.99 £9.99
0.5kg £16.99 14.99
0.75kg £16.99 £16.99
1.0kg £16.99 £19.99
1.5kg £16.99 £22.99
2.0kg £16.99 £24.99
4.0kg £24.99 N/A

 

EUROPE

Order Weight DPD 7-14 Days Royal Mail International Tracked UPS 7-14 Days
0.25kg £11.99 £9.99 £49.99
0.5kg £11.99 £12.99 £49.99
0.75kg £11.99 £14.99 £49.99
1.0kg £11.99 £17.99 £49.99
1.5kg £11.99 £19.99 £49.99
2.0kg £11.99 £21.99 £49.99
4.0kg £19.99 N/A £49.99

 

 REST OF WORLD

Order Weight Royal Mail International Tracked
0.25kg £9.99
0.5kg £14.99
0.75kg £16.99
1.0kg £19.99
1.5kg £22.99
2.0kg £24.99
4.0kg N/A

 

If you are unhappy with your purchase, please return it to us within 180 days of receipt. To be eligible for a return, your item must be in the same condition that you received it, unworn or unused, with tags, and in its original packaging.

For more information regarding our returns policy please visit our Returns Page

Washing instructions for Sub Zero base layers are printed on a white silk tag stitched to the back neck and can also be found knitted in to the waist band. Please follow these instructions carefully as failure to comply with them will make your guarantee void. If you have removed the tag or are unsure of the washing symbol meaning, the full washing instructions can be found below.

  • Machine wash or hand wash in water not exceeding 40°C or 105°F
  • You can use a mild washing detergent but ideally you want to use a base layer specific washing treatment 
  • Wash dark colours separately, do not bleach, do not use fabric conditioners
  • These base layers can be spun dry in a washing machine
  • Do not tumble dry. These base layers will quickly dry on a line or airer as they retain very little water once spun/rung out. 
  • Do not dry clean
  • Regular ironing may be performed at a low setting (110°C, 230°F) only, but we advise against it.

 

GENERAL WASHING TIPS
When you go to wash any garment with a zip, ensure it is done up fully otherwise the exposed teeth may cause harm in the wash cycle. The same can be said for garments containing Velcro. Your best course of action would be to wash these garments either by hand or on their own in a washing machine.

With the advancement in detergent technology, you very rarely need to wash any garments these days above 30°C. It is better to use a specific anti-bacterial wash-in treatment rather than increasing the temperature.

A lot of Sub zero products, especially the base layers and mid layers, can be ironed on a low temperature setting. We would advise against this as the heat settings on irons are not always reliable. In any case, the stretch properties of synthetics helps reduce creases in the wash and if there are any afterwards, they often drop out when worn.

Like most synthetics, Sub Zero fabrics will melt or burn if exposed to flame or direct heat. They are not flame resistant; do not use them near ANY direct source of heat or flame. This includes some of our merino wool products that contain a small percentage of synthetic yarn.

  • Thermal Efficiency: Advanced polyamide Factor 1 fabric construction retains heat whilst wicking away moisture.
  • Lightweight & Breathable: Ensures unrestricted movement and optimal temperature regulation.
  • High Wicking: hydrophilic treatment within the yarn actively transports moisture away from the skin.
  • Set-In Sleeves: Maximises wicking and provides a superior fit.
  • Generous Length: Helps prevent lower back exposure during activities.
  • Unisex Design: Tailored for both men and women for versatile wear.
  • Flatlock Seams: Minimises chafing and enhances comfort during extended use.
  • Easy Care: Machine washable and quick drying.
  • Brand: Sub Zero
  • SKU: SZF1SS
  • TOG: 0.42
  • Fabric: 100% Polyamide
  • Average weight: 140g / 4.9oz
  • Fit: Snug
  • Layer: First - next to the skin
  • Size availability: XSmall-XLarge
  • Colour: Khaki, Black, White, Pine Green
  • Fabric treatments: Hydrophilic
  • Washing instructions: 40°C wash with mild detergent, do not tumble dry, iron on low setting
  • Made in: Great Britain

 

We ship worldwide using Royal Mail, UPS & DPD. Please use the tables below as a guide for working out the shipping prices to your address. Please be aware that the product weights stated in the listings are for the products themselves, not the final weight when packaging is included. Our system will automatically calculate this and provide a total order weight during checkout. 

If you are unable to complete the checkout process when coming to choose a shipping option, then your order may be over the shipping weight limit for your address. Please call us on +44 (0)116 2402634 or email us at sales@subzero.co.uk and we can give you a custom shipping quote. 

For more detailed information regarding our shipping process please visit our comprehensive Shipping Page

UNITED KINGDOM

*All UK orders over £50 are shipped free of charge

Order Weight Royal Mail Tracked 24 Royal Mail Tracked 48 Royal Mail Guaranteed Before 1pm DPD Next Day
0.5kg £5.49 £3.99 £9.99 £8.99
1.0kg £6.49 £4.99 £11.99 £8.99
1.5kg £6.49 £4.99 £13.99 £8.99
2.0kg £6.49 £4.99 £13.99 £8.99
10.0kg N/A N/A N/A £8.99

 

* Royal Mail guaranteed service and DPD next day service is not available for Jersey, Guernsey, Isle of Man and Northern Ireland.

USA & CANADA

*All USA & Canada orders over £200 are shipped free of charge

Order Weight DPD 7-14 Days Royal Mail International Tracked
0.25kg £16.99 £9.99
0.5kg £16.99 14.99
0.75kg £16.99 £16.99
1.0kg £16.99 £19.99
1.5kg £16.99 £22.99
2.0kg £16.99 £24.99
4.0kg £24.99 N/A

 

EUROPE

Order Weight DPD 7-14 Days Royal Mail International Tracked UPS 7-14 Days
0.25kg £11.99 £9.99 £49.99
0.5kg £11.99 £12.99 £49.99
0.75kg £11.99 £14.99 £49.99
1.0kg £11.99 £17.99 £49.99
1.5kg £11.99 £19.99 £49.99
2.0kg £11.99 £21.99 £49.99
4.0kg £19.99 N/A £49.99

 

 REST OF WORLD

Order Weight Royal Mail International Tracked
0.25kg £9.99
0.5kg £14.99
0.75kg £16.99
1.0kg £19.99
1.5kg £22.99
2.0kg £24.99
4.0kg N/A

 

If you are unhappy with your purchase, please return it to us within 180 days of receipt. To be eligible for a return, your item must be in the same condition that you received it, unworn or unused, with tags, and in its original packaging.

For more information regarding our returns policy please visit our Returns Page

Washing instructions for Sub Zero base layers are printed on a white silk tag stitched to the back neck and can also be found knitted in to the waist band. Please follow these instructions carefully as failure to comply with them will make your guarantee void. If you have removed the tag or are unsure of the washing symbol meaning, the full washing instructions can be found below.

  • Machine wash or hand wash in water not exceeding 40°C or 105°F
  • You can use a mild washing detergent but ideally you want to use a base layer specific washing treatment 
  • Wash dark colours separately, do not bleach, do not use fabric conditioners
  • These base layers can be spun dry in a washing machine
  • Do not tumble dry. These base layers will quickly dry on a line or airer as they retain very little water once spun/rung out. 
  • Do not dry clean
  • Regular ironing may be performed at a low setting (110°C, 230°F) only, but we advise against it.

 

GENERAL WASHING TIPS
When you go to wash any garment with a zip, ensure it is done up fully otherwise the exposed teeth may cause harm in the wash cycle. The same can be said for garments containing Velcro. Your best course of action would be to wash these garments either by hand or on their own in a washing machine.

With the advancement in detergent technology, you very rarely need to wash any garments these days above 30°C. It is better to use a specific anti-bacterial wash-in treatment rather than increasing the temperature.

A lot of Sub zero products, especially the base layers and mid layers, can be ironed on a low temperature setting. We would advise against this as the heat settings on irons are not always reliable. In any case, the stretch properties of synthetics helps reduce creases in the wash and if there are any afterwards, they often drop out when worn.

Like most synthetics, Sub Zero fabrics will melt or burn if exposed to flame or direct heat. They are not flame resistant; do not use them near ANY direct source of heat or flame. This includes some of our merino wool products that contain a small percentage of synthetic yarn.

Factor 1 Unisex Short Sleeve Base Layer Tops are the perfect choice for those seeking lightweight, high-performance thermal underwear for active outdoor adventures.

Made from 100% polyamide ribbed fabric with advanced hydrophilic treatment, this base layer is designed to wick moisture away from your skin, keeping you dry and comfortable in all conditions. Its stretchy tubular construction offers a snug, flexible fit that moves with you, while the set-in sleeves ensure comfort around the shoulders and armpits.

With a generous body length, this top stays securely tucked in, preventing exposure around the lower back. Ideal for a wide range of activities—from hiking and skiing to camping—this versatile short sleeve top provides the perfect balance of comfort, warmth, and moisture control.

Whether worn on its own in milder weather or layered with other Sub Zero Mid Layer Thermals in colder conditions, the Factor 1 Short Sleeve Base Layer Top is a reliable and durable addition to your outdoor wardrobe.

Please note: These are end of line garments. There may be some slight colour variations where they have been folded, and some may have different versions of our logo, but apart from this these base layers are perfect. We have greatly reduced the price to reflect this.

Scroll down the page for further product details, technical information, sizing, shipping and any washing instructions.

Gift ideas under £20

STOCKING FILLERS

Try before you buy

RETAIL STORE

50% OFF hooded jackets

WITH CODE: DOWN
FREE UK Shipping
On all orders over £50
Quick Delivery
All orders will be delivered within 2-6 business days
Hassle-Free exchange
180 days return policy
5.0 Google Reviews
Customer satisfaction #1 priority