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805-543-1676 | 10-6 daily, 11-4 Sunday | The Switchback

Clothing
Footwear
- Hiking
  - Hiking Boots
  - Hiking Shoes
- Running
  - Trail Runners
  - Running Shoes
- Climbing
  - Climbing Shoes
  - Approach Shoes
- Snow
  - Ski Boots
  - Snowboard Boots
- Casual & Sandals
- Socks & Insoles
  - Socks
  - Insoles
  - Gaiters
Hike & Camp
Climb
- Climbing Gear
Ski & Snow
Racks & Travel
- Racks
- Bags & Luggage
Accessories
Other
- Gifts & Fun
- Essentials
Sale
Rentals
The Switchback
Brands
- A-D
  - Altra
  - Arc'teryx
  - Black Diamond
  - Burton
  - Camelbak
  - Cotopaxi
  - Dakine
  - Darn Tough
- G-K
  - Goodr
  - Hestra
  - Hydro Flask
  - Jones Snowboards
  - K2 Sports
  - Kuhl
- L-P
- S-Z
  - Smartwool
  - Smith Optics
  - The North Face
  - Thule
  - Toad&Co
  - Vuori
  - Yakima
  - YETI
- All Brands

Baselayer Bottoms

Home › Baselayer Bottoms

14 products

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Baselayer Bottom (14)

Brand

Hot Chillys (4)
Outdoor Research (0)
Patagonia (0)
Smartwool (10)

Size

XXS (3)
XS (15)
S (19)
M (24)
L (23)
XL (14)
XXL (1)
1X (1)
2x (1)

Smartwool Men's Classic Thermal Merino Base Layer Crew - Black

Smartwool Men's Classic Thermal Merino Base Layer Crew

Regular Price: from $115.00

Sale Price: from $115.00
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Unit Price: per

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Smartwool Women's Classic Thermal Merino Base Layer Crew - Black

Smartwool Women's Classic Thermal Merino Base Layer Crew

Regular Price: from $115.00

Sale Price: from $115.00
Regular Price

Unit Price: per

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Cart Error: Some items became unavailable. Update the quantity and try again.

Smartwool Women's Classic Thermal Merino Base Layer Bottom - Black

Smartwool Women's Classic Thermal Merino Base Layer Bottom

Regular Price: from $115.00

Sale Price: from $115.00
Regular Price

Unit Price: per

Added to Cart: View Cart or Continue Shopping.

Cart Error: Some items became unavailable. Update the quantity and try again.

Smartwool Kids' Classic Thermal Merino Base Layer Crew - Garden Pink Heather

Smartwool Kids' Classic Thermal Merino Base Layer Crew

Regular Price: $65.00

Sale Price: $65.00
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Unit Price: per

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Smartwool Kids' Classic Thermal Merino Base Layer Bottom - Winter Sky Heather

Smartwool Kids' Classic Thermal Merino Base Layer Bottom

Regular Price: $65.00

Sale Price: $65.00
Regular Price

Unit Price: per

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Smartwool Men's Classic All-Season Merino Base Layer Crew - Iron Heather

Smartwool Men's Classic All-Season Merino Base Layer Crew

Regular Price: $100.00

Sale Price: $100.00
Regular Price

Unit Price: per

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Smartwool Men's Classic All-Season Merino Base Layer Bottom - Iron Heather

Smartwool Men's Classic All-Season Merino Base Layer Bottom

Regular Price: $100.00

Sale Price: $100.00
Regular Price

Unit Price: per

Added to Cart: View Cart or Continue Shopping.

Cart Error: Some items became unavailable. Update the quantity and try again.

Hot Chillys Men's Pepperskins Bottom - Black

Hot Chillys Men's Pepperskins Bottom

Regular Price: $40.00

Sale Price: $40.00
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Unit Price: per

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Hot Chillys Women's Pepperskins Bottom - Black

Hot Chillys Women's Pepperskins Bottom

Regular Price: $40.00

Sale Price: $40.00
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Unit Price: per

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Hot Chillys Women's Pepperskins Crewneck - Black

Hot Chillys Women's Pepperskins Crewneck

Regular Price: $40.00

Sale Price: $40.00
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Unit Price: per

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Hot Chillys Men's Pepperskins Crewneck - Black

Hot Chillys Men's Pepperskins Crewneck

Regular Price: $40.00

Sale Price: $40.00
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Smartwool Men's Intraknit Thermal Merino Base Layer Crew - Black-White

Smartwool Men's Intraknit Thermal Merino Base Layer Crew

Regular Price: $150.00

Sale Price: $150.00
Regular Price

Unit Price: per

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Smartwool Men's Intraknit Thermal Merino Base Layer Bottom - Black-White

Smartwool Men's Intraknit Thermal Merino Base Layer Bottom

Regular Price: $150.00

Sale Price: $150.00
Regular Price

Unit Price: per

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Smartwool Men's Intraknit Thermal Merino Base Layer 3/4 Bottom - Charcoal Heather-Black

Smartwool Men's Intraknit Thermal Merino Base Layer 3/4 Bottom

Regular Price: $120.00

Sale Price: $120.00
Regular Price

Unit Price: per

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Showing items 1-14 of 14.

About Us

The Mountain Air is a family-owned, specialty outdoor retail store located on the Central Coast of California. Since 1975, we’ve been helping all people at all skill levels explore and enjoy the outdoors.

Call us at 805-543-1676.

Text us at 805-242-2687.

Email us at customerservice@themountainair.com.

667 Marsh Street Suite D
San Luis Obispo CA 93401

Shipping Disclaimer

We reserve the right to change or charge shipping costs based on package size, weight, and distance. We will reach out if different or additional charges are necessary, and appreciate your understanding of our location in San Luis Obispo, California.

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