SKU: F05000400-110-101

FZN Merino Pant

Name: FZN Merino Pant
Brand: 509
SKU: F05000400-110-101
Price: 99.95 USD
Availability: InStock

$99.95 USD

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Apex Red Black

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FZN stands for Five Zero Nine, not frozen, and that’s exactly how you’ll feel in the 509 FZN Merino Pant. This base layer pant provides versatile midweight warmth with a high-performance Alpine Merino wool blend that’s naturally breathable, fast-drying, and odor-repellent—all without the itch. It’s far superior to conventional fabrics and compared to grandpa’s wool knickers, it’s like upgrading your sled from his 1978 Panther to a PRO-RMK®.

Key Features

Materials: Alpine Merino - 250 GSM 20 micron wool, blended with 40% Bamboo Viscose, and 10% nylon for structure and durability
Warmth: LVL [2]
WARNING for California Residents

Merino Wool

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You're going to LOVE the fit. Try it on and experience our perfect fit. If you don't love it, send it back in new and unused condition within 30 days for an exchange or full refund*. Risk free.

Scroll to the right to see more sizes

	X-Small	Small	Medium	Large	X-Large	2X-Large	3X-Large
Men's Chest	34 - 36	36 - 38	39 - 41	42 - 44	45 - 47	48 - 50	52 - 54
Sleeve	27	28	30	32	34	36	36
Waist	30	32	34	36	38	40	42
Inseam	29	30	31	32	33	34	34
Women's Chest	30	32	34	36	38	40	n/a
Sleeve	24	26	28	30	32	34	n/a
Waist	28	30	32	34	36	38	n/a
Inseam	29	30	32	34	36	38	n/a

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BENEFITS OF MERINO WOOL

Excellent Insulation: Merino wool is a natural insulator, providing unparalleled warmth even in cold and wet conditions. The fibers trap air, creating an insulating layer that keeps body heat close, ensuring you stay cozy and comfortable during your outdoor adventures. Merino wool is a natural insulator, providing unparalleled warmth even in cold and wet conditions. The fibers trap air, creating an insulating layer that keeps body heat close, ensuring you stay cozy and comfortable during your outdoor adventures.
Moisture and Temperature Management: Merino wool has a unique ability to wick moisture away from the skin and regulate body temperature. Whether you're working up a sweat or facing frigid temperatures, Merino wool keeps you dry and comfortable by managing moisture and thermal regulation effectively. When you wear merino wool, you can trust that its unique properties will keep you dry and comfortable. It has the ability to wick moisture away from your skin, ensuring that you stay dry even when you're working up a sweat or facing frigid temperatures.
Breathable and Fast-Drying: The breathable nature of Merino wool allows excess heat and moisture to escape, preventing overheating and discomfort. Additionally, it dries quickly, making it an excellent choice for activities that involve varying levels of intensity and conditions. Merino wool's breathable nature enables the escape of excess heat and moisture, ensuring that you never experience discomfort or overheating. This makes it an ideal option for activities that involve varying levels of intensity and conditions.
Odor-Repellent: Merino wool has natural antimicrobial properties that resist the buildup of odor-causing bacteria, keeping you fresh and odor-free even after prolonged use. These natural antimicrobial properties of Merino wool make it an ideal choice for those who want to stay fresh and odor-free, even after prolonged use.

Overall rating: 5.0 / 5 from 10 reviews.

AI Generated Review Summary

Summary topics

Review topics: ["layer"].

Review highlights

Reviews

Nice fit.

"Size is true"

— Jason D. (5/5)

Super warm and cozy

"Went ice fishing for 3 days. Had the top and bottoms on and was nice and warm."

— Kyle H. (5/5)

Best money you can spend in the the backcountry

"100% required gear"

— Sam B. (5/5)

Pants were great but XL

"Pants were great but XL shirt rubbed chest and pulled hair."

— Yolanda M. (5/5)

Excellent merino base layer paints

"Best pair of base layers that I own. Nice merino wool blend."

— Garrett S. (5/5)

Comfy and Warm

"I ordered the Merino top and bottom and have used them both a handful of times and love the fit, theyre stretchy and soft and work very well!"

— Andrew M. (5/5)

Still warm in zubzero temps.

"Still warm in zubzero temps."

— Andrey B. (5/5)

509 Rocks

"Amazingly soft, no itch. Highly recommend."

— Robert F. (5/5)

These feel awesome against the

"These feel awesome against the skin, non-irritating and you pretty much forget you are wearing these. Also keeps you warm on those colder days and yet cool enough on the warmer days"

— Kwai B. (5/5)

Awesome!

"These pants work great under my gear. It is well made and the material is great. Highly recommended!"

— Ken (5/5)

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