Merino SF100 Long Sleeve

Sand / S

$110

✓ Extended Free Returns
✓ Free Returns Within 60 Days

✓ Extended Free Returns ✓ Free Returns Within 60 Days

Merino SF100 Long Sleeve

$110

Rated 4.7 out of 5

Based on 30 reviews

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How it works?

For this item, you can order your usual size. If it doesn't fit, you can exchange it.

Unsure about something? Email support@seadon.co and let us help you find your perfect fit.

cm in

Measurement	S	M	L	XL	XXL	3XL
AChest Width	48.0 18.9	50.5 19.9	53.0 20.9	55.5 21.9	58.5 23.0	61.5 24.2
BBottom Opening	47.0 18.5	49.5 19.5	52.0 20.5	54.5 21.5	57.5 22.6	60.5 23.8
CFront Body Length	69.0 27.2	71.0 28.0	73.0 28.7	75.0 29.5	77.0 30.3	79.0 31.1
DNeck Width Collar	17.5 6.9	18.0 7.1	18.5 7.3	19.0 7.5	19.5 7.7	20.0 7.9
EFront Neck Drop	9.5 3.7	10.0 3.9	10.5 4.1	11.0 4.3	11.5 4.5	12.0 4.7
FSleeve Length	62.5 24.6	63.5 25.0	64.5 25.4	65.5 25.8	66.5 26.2	67.5 26.6
GWidth Of Shoulders	41.0 16.1	43.0 16.9	45.0 17.7	47.0 18.5	49.0 19.3	51.0 20.1

The values are given in cm The values are given in inch

100% natural fabric with an ultrasoft hand feel
Stay cool in summer and warm in winter.
Stays fresh for up to 7 days (or more!)
Water + Wrinkle resistant
Naturally antimicrobial
Ultralight, moisture wicking, and quick dry
Back neck hanging loop
Tagless neck print to avoid those itchy neck labels
Sun protection (UPF 30+)

100% Superfine RWS certified Merino Wool (18.5 microns)
150 g (5.29 oz) high-stretch rib jersey
Machine wash cold (gentle cycle). Tumble dry low (if needed). Use wool detergent and line dry as recommended.

Responsibly sourced RWS-certified Merino Wool.
100% natural fiber
1% of sales made from this product gets donated back to nonprofits
Made responsibly in China
We are a Climate Neutral Company (climateneutral.org/brand/seadon)

1 Thermoregulating Rib Jersey

150g high-stretch rib jersey that adapts to temperature: cool in summer, warm in winter.

2 7-Day Odor Resistance

Naturally antimicrobial fibers keep it fresh for 7+ days of continuous wear without washing.

3 Natural Water & Wrinkle Shield

Wool’s natural elasticity resists wrinkles and sheds water on misty days.

4 100% Superfine Merino Wool

Ultra-soft 18.5-micron RWS-certified Merino wool, 100% natural and biodegradable.

5 Himalaya-Tested Endurance

Field-tested for 25 consecutive days in the Himalayas: resilient, lightweight comfort.

6 Tagless Comfort & Sun Shield

Tagless neck for zero itch, back-neck loop for quick drying, plus natural UPF 30+ coverage.

FOR MULTI-DAY ADVENTURES

TESTED 25 DAYS STRAIGHT IN THE HIMALAYAS

Made from 100% RWS-certified superfine Merino wool, SF100 combines natural warmth, breathability and odor resistance in one lightweight layer. Field-tested through 25 consecutive days in the Himalayas, it’s built for adventure far beyond the ordinary.

Himalayan Tested

Worn for 25 days straight in the Himalayas. The more you wear it, the better it gets.

Ultrasoft Superfine Wool

18.5-micron 100% Merino wool with an ultrasoft hand feel — no itch, all comfort.

7+ Days Fresh

Naturally antimicrobial and odor-resistant. Stays fresh for a week or more without washing.

All-Season Thermoregulation

Stay cool in summer and warm in winter with natural moisture-wicking and quick-dry performance.

Environmental and social impact

We donate 1% to nonprofit the planet.

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Write a Review

average rating 4.7 out of 5

Based on 30 reviews

5 Stars

23 Reviews
4 Stars

5 Reviews
3 Stars

1 Review
2 Stars

1 Review
1 Star

0 Reviews

93% of reviewers would recommend this product to a friend

Fabric	Rated 4 out of 5
Quality	Rated 4 out of 5
Sizing	Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Big

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30 Reviews

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Reviewed by J L.

Verified Buyer

Reviewing

Seadon® Men's Merino SF100 Long Sleeve Tee - Jungle Green

I recommend this product

Size Purchased

L

Rated 5 out of 5

Review posted

Great feel

It fits nice and has a great feel to it.

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Fabric	Rated 5 out of 5
Quality	Rated 5 out of 5
Sizing	Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Big

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Reviewed by Rick P.

Verified Buyer

Reviewing

Seadon® Men's Merino SF100 Long Sleeve Tee - Jet Black

I recommend this product

Size Purchased

XL

Rated 4 out of 5

Review posted

Great material

This shirt feels great and is good addition to my travel wardrobe for cooler days. The feedback I’ve been getting is that it’s not as good a fit as my other shirts so I only wear it under a jacket.

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Fabric	Rated 5 out of 5
Quality	Rated 4 out of 5
Sizing	Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Big

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Reviewed by Todd E.

Verified Buyer

Reviewing

Seadon® Men's Merino SF100 Long Sleeve Tee - Jet Black

I recommend this product

Size Purchased

XL

Rated 5 out of 5

Review posted

Men’s shirt is outstanding

True to size fit and superior quality.

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Fabric	Rated 5 out of 5
Quality	Rated 5 out of 5
Sizing	Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Big

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Reviewed by stacey e.

Verified Buyer

Reviewing

Seadon® Men's Merino SF100 Long Sleeve Tee - Jet Black

I recommend this product

Size Purchased

M

Rated 5 out of 5

Review posted

Feels pretty thin...

The material is very soft and stretchy but much thinner than I expected (even for a base layer) and I'm not convinced it will hold up...but the makers seem to be--offered a replacement if the t-shirt didn't make it through the winter season unscathed. I'm impressed the company is willing to stand behind their product to hat extent.

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Fabric	Rated 4 out of 5
Quality	Rated 4 out of 5
Sizing	Rated -1 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Big

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Reviewed by steve h.

Verified Buyer

Reviewing

Seadon® Men's Merino SF100 Long Sleeve Tee | Graphic - Night Peak Camp

I recommend this product

Rated 4 out of 5

Review posted

Awesome shirt

I ordered this through the Kickstarter campaign. The sizing information helped me choose a perfect fit and the shirt is remarkably comfortable. I am looking forward to wearing it in the summer as it is very lightweight and should be a good choice for my backcountry canoe camping trips.

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