SIMIYA Men’s Thermal Underwear Set, Fleece Lined Base Layer, Black

£23.99 (as of 05/02/2026 04:30 PST - DetailsProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply to the purchase of this product.)

SIMIYA men’s thermal underwear set with a long sleeve base layer top and long johns bottoms. It features fleece lining, 4-way stretch fabric, a fly opening and a cut-to-length option for the leg and arm openings, with black colour and cold weather use described.

SKU: B0B58JXPPC Category:

Quick Summary

SIMIYA men’s thermal underwear set is a long sleeve base layer and long johns set for cold weather wear. It features a fleece lining and a black finish, with the set described as suitable for winter use and outdoor activities.

The fabric is listed as a blend of 90% polyester and 10% spandex. The set also includes a tag-less design, a fly/pee hole in the thermal pant, and a cut-to-length option for the leg and arm openings with a stated maximum tailoring range of 1.18 inches.

Who It Is Best For

This set is for buyers looking for thermal tops and bottoms to wear as a base layer in colder conditions. It may suit those who want a fleece lined option with stretch, a fly opening in the bottoms, and the ability to adjust the leg and arm openings to length.

Key Details

DetailVerified information and buyer relevance
BrandSIMIYA.
Product typeMen’s thermal underwear set, including a thermal base layer top and long johns bottoms.
ColourBlack.
Fabric blend90% polyester and 10% spandex.
LiningFleece lined inside for added warmth in cold conditions.
Fit features4-way stretch fabric and a tag-less design for unrestricted movement and reduced skin irritation.
Bottoms detailFly/pee hole included in the thermal pant.
Cut-to-length optionLeg and arm openings can be cut to the best length, with a stated maximum tailoring range of 1.18 inches.

Why Buyers Choose It

  • The fleece lining is a clear thermal feature for colder weather wear.
  • The 4-way stretch fabric supports movement without adding stiffness.
  • The cut-to-length design gives some adjustment at the arm and leg openings.
  • The fly opening in the bottoms adds a practical detail for everyday use.

What To Know Before You Buy

Check the size chart before ordering, as fit is important for thermal base layers. The set is described as black and as a men’s top and bottoms combination, so confirm that this is the style and colour you want. If you plan to use the cut-to-length feature, review the stated 1.18 inch tailoring range before trimming.

Common Buyer Questions

Does this set include both a top and bottoms?
Yes. It is a thermal underwear set with long sleeve tops and long johns bottoms.

Is the fabric stretchy?
Yes. The set uses 4-way stretch fabric for unrestricted movement.

Can the openings be shortened?
Yes. The leg and arm openings can be cut to length, with a stated maximum tailoring range of 1.18 inches.

Does the bottoms design include a fly opening?
Yes. The thermal pant includes a fly/pee hole.

Final Buying View

If you want a men’s thermal underwear set with fleece lining, stretch fabric and a cut-to-length option, this SIMIYA set gives those features in a black base layer style. Check the size chart and the tailoring range before choosing your size.

This set is described for cold weather use, so it is worth comparing the listed features with your expected fit and layering needs before ordering.

Brand

SIMIYA

Manufacturer

SIMIYA

Product Group

Apparel

Model

WU03-2

Color

Black

Item Weight

0.90 pounds

Size

M

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