For environments that demand more warmth without adding bulk, Massif® Midweight Base Layers give thermal performance while still allowing movement. These layers are designed to work seamlessly within a full protective layering system — keeping you regulated and mission-ready in transitional and cold-weather conditions.

Showing all 12 results

  • a men's olive green long-sleeve thermal shirt designed as a fitted base layer featuring a crew neck long sleeves that reach to the wrist.

    Inversion Crew Midweight (FR)

    $58.22

    The Inversion Crew (Midweight) base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • the Inversion Long Sleeve Crew Neck Base Layer in a heathered olive green color displayed on a white background. This long-sleeved shirt has a crew neckline and a close fit. The fabric appears to be a soft insulating knit.the Inversion Long Sleeve Crew Neck Base Layer in black displayed on a white background. This long-sleeved shirt has a crew neckline and a close fit. The fabric appears to be a soft insulating knit.

    Inversion Crew Midweight (FR)

    $62.35

    The Inversion Crew (Midweight) base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • The Women's Long Sleeve Crew Neck Base in tan displayed on a white background. This long-sleeved shirt has a crew neckline and a close fit. The fabric appears to be a soft insulating knit.

    Inversion Crew Midweight – Women’s Fit (FR)

    $62.35

    The Inversion Crew (Midweight) – Women’s Fit base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability. This fit has been created from the ground up to give female end users a well-fitting garment so that they can constantly deliver.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • The Women's Inversion Crew Lightweight long-sleeved top in black displayed on a white background. The top has a high close-fitting crew neckline and a fitted silhouette. The fabric appears to be a lightweight stretchy knit.

    Inversion Crew Midweight – Women’s Fit (FR)

    $62.35

    The Inversion Crew (Midweight) – Women’s Fit base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability. This fit has been created from the ground up to give female end users a well-fitting garment so that they can constantly deliver.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A pair of Massif Inversion Bottoms Base Layer in tan displayed on a white background. These long underwear pants have a close fit with an elastic waistband and a fly opening. The fabric appears to be a soft insulating knit.A pair of Massif Inversion Bottoms Base Layer in black displayed on a white background. These long underwear pants have a close fit with an elastic waistband and a fly opening. The fabric appears to be a soft insulating knit.

    Inversion Bottom Midweight (FR)

    $58.55

    The Inversion Bottom (Midweight) base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • a pair of men's olive green long underwear also known as thermal pants or long johns fitted with full-length cut that extends from the waist to the ankles featuring an elastic waistband a functional front pouch (fly) for convenience.

    Inversion Bottom Midweight (FR)

    $54.68

    The Inversion Bottom (Midweight) base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A pair of Massif Inversion Bottoms Base Layer in tan displayed on a white background. These long underwear pants have a tight silhouette fit with an elastic waistband and a fly opening. The fabric appears to be a soft insulating knit.The back view of a pair of Inversion Bottoms Base Layer in tan displayed on a white background. These long underwear pants have a close fit with an elastic waistband visible at the top.

    Inversion Bottom Midweight – Women’s Fit (FR)

    $58.55

    The Inversion Bottom (Midweight) – Women’s Fit base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability. This fit has been created from the ground up to give female end users a well-fitting garment so that they can constantly deliver.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A pair of Women's Inversion Bottoms Base Layer in black displayed on a white background. These long underwear pants have a close silhouette fitting with an elastic waistband and a fly opening. The fabric appears to be a soft insulating.

    Inversion Bottom Midweight – Women’s Fit (FR)

    $58.55

    The Inversion Bottom (Midweight) – Women’s Fit base layer is a premier flame-resistant garment with an advanced tri-blend yarn system that provides unparalleled performance across mild to cool environments. Inversion is inherently sweat-wicking and is designed to create a quick-drying and breathable garment, and the inclusion of spandex gives the end user an improved range of motion, superior comfort, and extraordinary recovery for after-wash durability. This fit has been created from the ground up to give female end users a well-fitting garment so that they can constantly deliver.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A Massif HotJohns Long Sleeve Crew Neck Base Layer in a heathered olive green color displayed on a white background. This long-sleeved shirt has a crew neckline and a close fit. The fabric appears to be a soft insulating.A Massif HotJohns Long Sleeve Crew Neck Base Layer in black displayed on a white background. This long-sleeved shirt has a crew neckline and a close fit. The fabric appears to be a soft insulating.

    HotJohns® Crew (FR)

    $142.81

    The HotJohns® Crew is made to fit the needs of the end-user depending on the operation as a base layer that can be worn next to skin or over a Massif® Cool Knit®. The HotJohns® Crew is a midweight base layer that is streamlined for easy layering, is highly breathable, and wicks moisture away to keep you warm and dry. This proprietary flame-resistant midweight Massif® knit fabric features DuPont™ Kevlar® and Nomex® to provide warmth without weight.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • The Women's HotJohns Long Sleeve Crew Neck Base Layer in black. This long-sleeved shirt has a crew neckline with the Massif logo visible. It has a more fitted silhouette. The fabric appears to be a soft insulating.The back view of the Women's HotJohns Long Sleeve Crew Neck Base Layer in black. This long-sleeved shirt has a crew neckline and a fitted silhouette. Raglan sleeves are visible on the back.

    HotJohns® Crew – Women’s Fit (FR)

    $142.81

    The HotJohns® Crew – Women’s Fit is made to fit the needs of the female end-user depending on the operation as a base layer that can be worn next to skin or over a Massif® Cool Knit®. The HotJohns® Crew is a midweight base layer that is streamlined for easy layering, is highly breathable, and wicks moisture away to keep you warm and dry. This proprietary flame-resistant midweight Massif® knit fabric features DuPont™ Kevlar® and Nomex® to provide warmth without weight.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A pair of Massif HotJohns Bottoms Base Layer in a olive green displayed on a white background. These long underwear pants have a close fit with an elastic waistband and a fly. The fabric appears to be a soft insulating.A pair of Massif HotJohns Bottoms Base Layer in black displayed on a white background. These long underwear pants have a close fit with an elastic waistband and a fly. The fabric appears to be a soft insulating.

    HotJohns® Bottom (FR)

    $140.85

    The HotJohns® Bottom is made to fit the needs of the end-user depending on the operation as a base layer that can be worn next to skin or over a Massif® Cool Knit®. The HotJohns® Bottom is a midweight base layer that is streamlined for easy layering, is highly breathable, and wicks moisture away to keep you warm and dry. This proprietary flame-resistant midweight Massif® knit fabric features DuPont™ Kevlar® and Nomex® to provide warmth without weight.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page
  • A Women's pair of Massif HotJohns Bottoms Base Layer in black displayed on a white background. These long underwear pants have a close fit with an elastic waistband and a fly. The fabric appears to be a soft insulating.The back view of a Women's pair of Massif HotJohns Bottoms Base Layer in black displayed on a white background. These long underwear pants have a close legging-like fit with an elastic waistband.

    HotJohns® Bottom – Women’s Fit (FR)

    $140.85

    The HotJohns® Bottom – Women’s Fit is made to fit the needs of the female end-user depending on the operation as a base layer that can be worn next to skin or over a Massif® Cool Knit®. The HotJohns® Bottom is a midweight base layer that is streamlined for easy layering, is highly breathable, and wicks moisture away to keep you warm and dry. This proprietary flame-resistant midweight Massif® knit fabric features DuPont™ Kevlar® and Nomex® to provide warmth without weight.

    Safe-to-Fly (StF) Approved by U.S. Air Force – Air National Guard

    Select optionsDone This product has multiple variants. The options may be chosen on the product page

GEAR UP FOR THE MISSION AHEAD WITH MASSIF®

Massif® makes every design, manufacturing, and sourcing decision to bring our gear to life with clear intention. While the type of protection that members of SAR communities and our country’s armed forces require is unique and challenging, we take pride in the fact that we maintain a tight focus on meeting and exceeding the needs of our end users. From the first NOMEX® fleece suit that Massif®’s founder, Randy Benham, hand-sewed in his parent’s garage to the cutting-edge new offerings – Massif is committed to your protection.
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