A man wearing a Polartec Critter Birthday Suit is standing in front of some skis.
A man is zipping up the front of a Polartec Critter Birthday Suit while standing in front of some skis.
A man wearing a Polartec Critter Birthday Suit and holding the back flap open with his hand.
A Polartec Critter Birthday Suit laying flat on a rock showing the entire front with the arm holes, pockets and front zipper.
A swatch of orange material with the words Alpha Direct 60 Fire Opal in the center.
A swatch of blue material with the words Alpha Direct 90 Sapphire in the center.
A swatch of black material with the words Alpha Direct 120 Onyx in the center.
A swatch of black material with silver flecks and the words Alpha Direct 150 Silver Onyx in the center.
A swatch of blue material with the words Polartec ThermalPro Sapphire in the center.
Polartec log in red and black on a white background.
A man wearing a Polartec Critter Birthday Suit is standing in front of some skis.
A man is zipping up the front of a Polartec Critter Birthday Suit while standing in front of some skis.
A man wearing a Polartec Critter Birthday Suit and holding the back flap open with his hand.
A Polartec Critter Birthday Suit laying flat on a rock showing the entire front with the arm holes, pockets and front zipper.
A swatch of orange material with the words Alpha Direct 60 Fire Opal in the center.
A swatch of blue material with the words Alpha Direct 90 Sapphire in the center.
A swatch of black material with the words Alpha Direct 120 Onyx in the center.
A swatch of black material with silver flecks and the words Alpha Direct 150 Silver Onyx in the center.
A swatch of blue material with the words Polartec ThermalPro Sapphire in the center.
Polartec log in red and black on a white background.

Birthday Suit

from $219.00

Critter Birthday Suit: Rugged Performance for the Outdoors

Description

When you don’t want anything to freeze and fall off: The Critter Birthday Suit combines rugged, classic styling with modern, high-performance fabric technology. Built for demanding work or extended outdoor stays, this full-coverage suit delivers comprehensive protection and comfort without compromising mobility.

Constructed using a durable Polartec® fabric—such as Alpha Direct for high-output activities, or ThermalPro for exceptional warmth—the suit creates a thermal barrier that provides a superior warmth-to-weight ratio. Its sleeveless design ensures optimal flexibility with layering, keeping your core and legs consistently warm.

Despite its insulating power, the fabrics remain highly breathable and moisture-wicking, preventing overheating and the clammy feeling that comes from trapped sweat. Featuring two front pockets and a stand-up collar, the Birthday Suit is designed to withstand anything winter can throw at you.

Inspired, designed, and crafted with pride in Crested Butte, Colorado.

Features

  • Athletic fit

  • Stand-up collar

  • Generous arm holes

  • Two front pockets

  • Elastic waistband in back

  • Shirt-style seat flap opening for relief

  • Hemmed ankles

Materials

Polartec® Alpha Direct 60, 90 and 120 (100% recycled polyester)

or
Polartec® Alpha Direct 150 with Wool (63% polyester/33% wool/4% nylon) - LIMITED EDITION

or
Polartec® ThermalPro (100% recycled polyester)

Sizes - Inches

Chest Sleeves Waist Inseam

Small 34-36” 33” 28-30” 30”

Medium 38-40” 34” 32-34” 31”

Large 42-44” 35” 36-38” 32”

XLarge 46-48” 36” 40-42” 33”

XXLarge 50-52” 37” 44-46” 34”

𝗦izes - Centimeters

Chest Sleeves Waist Inseam

Small 86-91 84 71-76 76

Medium 97-102 86 81-86 79

Large 107-112 89 91-97 81

XLarge 117-122 91 102-107 84

XXLarge 127-132 94 112-117 86

Weight

Medium size for comparison:

Polartec® Alpha Direct 60 - 5 ozs./142 grams

Polartec® Alpha Direct 90 - 7.5 ozs./213 grams

Polartec® Alpha Direct 120 - 10.5 ozs./298 grams

Polartec® Alpha Direct 150 with Wool - 12 ozs./340 grams

Polartec® ThermalPro - 14.5 ozs./411 grams

Care Instructions

Alpha Direct

Hand wash cold. Lay flat to dry. Do not machine wash, bleach, iron, or dry clean. Avoid fabric softeners.

ThermalPro

Machine wash cold. Tumble dry on low. Do not bleach, iron, or dry clean. Avoid fabric softeners.

Size:
Material/Color:

Critter Birthday Suit: Rugged Performance for the Outdoors

Description

When you don’t want anything to freeze and fall off: The Critter Birthday Suit combines rugged, classic styling with modern, high-performance fabric technology. Built for demanding work or extended outdoor stays, this full-coverage suit delivers comprehensive protection and comfort without compromising mobility.

Constructed using a durable Polartec® fabric—such as Alpha Direct for high-output activities, or ThermalPro for exceptional warmth—the suit creates a thermal barrier that provides a superior warmth-to-weight ratio. Its sleeveless design ensures optimal flexibility with layering, keeping your core and legs consistently warm.

Despite its insulating power, the fabrics remain highly breathable and moisture-wicking, preventing overheating and the clammy feeling that comes from trapped sweat. Featuring two front pockets and a stand-up collar, the Birthday Suit is designed to withstand anything winter can throw at you.

Inspired, designed, and crafted with pride in Crested Butte, Colorado.

Features

  • Athletic fit

  • Stand-up collar

  • Generous arm holes

  • Two front pockets

  • Elastic waistband in back

  • Shirt-style seat flap opening for relief

  • Hemmed ankles

Materials

Polartec® Alpha Direct 60, 90 and 120 (100% recycled polyester)

or
Polartec® Alpha Direct 150 with Wool (63% polyester/33% wool/4% nylon) - LIMITED EDITION

or
Polartec® ThermalPro (100% recycled polyester)

Sizes - Inches

Chest Sleeves Waist Inseam

Small 34-36” 33” 28-30” 30”

Medium 38-40” 34” 32-34” 31”

Large 42-44” 35” 36-38” 32”

XLarge 46-48” 36” 40-42” 33”

XXLarge 50-52” 37” 44-46” 34”

𝗦izes - Centimeters

Chest Sleeves Waist Inseam

Small 86-91 84 71-76 76

Medium 97-102 86 81-86 79

Large 107-112 89 91-97 81

XLarge 117-122 91 102-107 84

XXLarge 127-132 94 112-117 86

Weight

Medium size for comparison:

Polartec® Alpha Direct 60 - 5 ozs./142 grams

Polartec® Alpha Direct 90 - 7.5 ozs./213 grams

Polartec® Alpha Direct 120 - 10.5 ozs./298 grams

Polartec® Alpha Direct 150 with Wool - 12 ozs./340 grams

Polartec® ThermalPro - 14.5 ozs./411 grams

Care Instructions

Alpha Direct

Hand wash cold. Lay flat to dry. Do not machine wash, bleach, iron, or dry clean. Avoid fabric softeners.

ThermalPro

Machine wash cold. Tumble dry on low. Do not bleach, iron, or dry clean. Avoid fabric softeners.