All measurements are in inches and reflect body measurements. If you are in between sizes, size up for comfort.
Got questions? Email us at info@freeflyapparel.com.
Men
Women
Toddler
Youth
Alpha Sizes
Numeric Sizes
Chest
Waist
Hip
Sleeve
S
30–31
36–38
30–32
34–37
32–33
M
32–33
38–40
32–34
37–39
33–34
L
34–35
41–43
35–37
40–42
34–35
XL
36–38
44–46
38–40
43–45
35–36
XXL
40
47–49
41–43
46–48
36–37
3XL
50–52
44–46
49–51
36–37
Alpha Sizes
Numeric Sizes
Bust
Waist
Hip
XS
0–2
32–33
25–26
35–36
S
4–6
34–35
27–28
37–38
M
8–10
36–37
29–30
39–40
L
12–14
38 1/2–40
31 1/2–33
41 1/2–43
XL
16
41 1/2–43
34 1/2–36
44 1/2–46
XXL
44 1/2–46
37 1/2–39
47 1/2–49
US Size
Height (IN)
Weight (LB)
2T
33–37
27–31
4T
38–42
33–37
6T
45–49
44–48
US Size
Height (IN)
Weight (LB)
XS/6–7
45–48
45–50
S/8–9
49–52
51–65
M/10–12
53–57
66–80
L/13–14
68–62
81–95
XL/15–16
63–66
96–110
*Learn how to find your true waist below.
Please find inseam length on specific product detail page.
Don’t let the timeless looks fool you—the Seawool Flannel packs a punch in the performance department. Built from Seawool fabric, a midweight brushed twill made from upcycled oyster shells and recycled plastic bottles, these flannels deliver many of the same benefits as our powered-by-bamboo styles: they’re temp-regulating, quick-dry, anti-odor, and oh-so-soft. Bonus points: all those recycled plastic bottles never get the chance to end up in our oceans. Adventure-ready, sustainable, and classically handsome? Sign us up.
One Size Doesn't Fit All
All measurements are in inches and reflect body measurements. If you are in between sizes, size up for comfort.
Got questions? Email us at info@freeflyapparel.com.
Men
Women
Toddler
Youth
Alpha Sizes
Numeric Sizes
Chest
Waist
Hip
Sleeve
S
30–31
36–38
30–32
34–37
32–33
M
32–33
38–40
32–34
37–39
33–34
L
34–35
41–43
35–37
40–42
34–35
XL
36–38
44–46
38–40
43–45
35–36
XXL
40
47–49
41–43
46–48
36–37
3XL
50–52
44–46
49–51
36–37
Alpha Sizes
Numeric Sizes
Bust
Waist
Hip
XS
0–2
32–33
25–26
35–36
S
4–6
34–35
27–28
37–38
M
8–10
36–37
29–30
39–40
L
12–14
38 1/2–40
31 1/2–33
41 1/2–43
XL
16
41 1/2–43
34 1/2–36
44 1/2–46
XXL
44 1/2–46
37 1/2–39
47 1/2–49
US Size
Height (IN)
Weight (LB)
2T
33–37
27–31
4T
38–42
33–37
6T
45–49
44–48
US Size
Height (IN)
Weight (LB)
XS/6–7
45–48
45–50
S/8–9
49–52
51–65
M/10–12
53–57
66–80
L/13–14
68–62
81–95
XL/15–16
63–66
96–110
*Learn how to find your true waist below.
Please find inseam length on specific product detail page.
Use the guide below with a fabric tape measure to find your measurements.
CHEST
Measure circumference from the widest part around chest, about 1” down from armpit.
SLEEVE
With arm slightly bent, measure from center back neck to shoulder, down arm to wrist bone.
TRUE WAIST
Measure around your natural waist, narrowest part of your torso.
HIP
Measure around the fullest part of your hips.
BUST
Measure circumference from the widest part around chest, about 1" down from armpit.
TRUE WAIST
Measure around your natural waist, narrowest part of your torso.
HIP
Measure around the fullest part of your hips.
Free Returns & Exchanges
If you try it and it doesn't fit, no problem. Returns and exchanges are free and easy.
Learn More
Materials & Care
Material Description: Brushed twill made from upcycled oyster shells and recycled plastic bottles
Material Contents: 57% Cotton / 40% Recycled Seawool Polyester / 3% Spandex
Fabric Weight (GSM): 177
Hang dry
Features
• Classic flannel shirt packed with sneaky performance
• Thermo-regulating, anti-odor, and quick-dry properties perfect for days on the water
• Left chest pocket perfect for stashing your shades
Size & Fit
Relaxed through the body for comfort and room to move
Shipping & Returns
Free standard shipping on all orders $150+
Free 30-day returns and 60-day exchanges on U.S. orders for unwashed, unworn items.
Final sale styles are not eligible for return or exchange.
Send gifts wrapped by adding on gift wrap at cart. We also offer free gift messaging.
Perfect for stashing your shades or other small essentials
Meet Seawool
SUSTAINABLE
B CORP CERTIFIED
For over a decade, we've been innovating with natural materials—bamboo, eucalyptus, and now oyster shells—to build our gear. As a family-founded company that lives for the outdoors, supporting our community and protecting our planet’s wild places are absolutely central to Free Fly’s purpose.
Husband really loves this flannel as a stand alone shirt and to layer! Not to heavy or stiff to be uncomfortable but nice and warm
What is your height? 5'10-6'0
What is your weight? 200-220
What size did you purchase? XL
For what activity do you recommend this product? Casual Wear, Travel, Hiking, Work
Chris P.
Verified Buyer
Rated 5 out of 5 stars
1 week ago
Reviewing
Men's Seawool Flannel Shirt - Deep Navy Deep Navy / XL
This Shirt Has No Business Being This Good
Let me preface this by saying I’ve owned a few flannels in my life. Some good, some questionable, some that looked great until you washed them and they shrank into something better suited for a medium-sized house cat.
I put it on and immediately felt like the kind of man who could chop firewood, quote Hemingway, identify six trout species by smell alone, and still be soft enough inside to cry politely at Pixar movies. It has the rare combination of rugged outdoors energy and “I moisturize regularly” refinement.
SeaWool? I don’t understand it. I don’t want to understand it. All I know is that this shirt feels like Poseidon personally blessed a sheep, whispered a lullaby to it, and Free Fly stole the resulting fibers to create the comfiest thing ever produced by humankind. The moment I wore it, my confidence went up 12%. My casting accuracy improved. My dog respected me more. My wife looked at me like, “Oh… you upgraded.
And to the Free Fly team — you already had my loyalty. Now you have my heart, wallet, and the top two shelves of my closet. This is the kind of shirt that ruins other shirts. Once you’ve worn SeaWool, cotton feels like sandpaper and every other flannel feels like it was designed by someone who hates joy.
What is your height? 5'10-6'0
What is your weight? 180-200
What size did you purchase? XL
For what activity do you recommend this product? Casual Wear
Frederic B.
Verified Buyer
Rated 5 out of 5 stars
3 weeks ago
Reviewing
Men's Seawool Flannel Shirt - Sandstone Sandstone / L
Comfortable
Soft but durable and a nice weight.
What is your height? 5'10-6'0
What is your weight? 160-180
What size did you purchase? L
For what activity do you recommend this product? Casual Wear
Bill D.
Verified Buyer
Rated 5 out of 5 stars
4 weeks ago
Reviewing
Men's Seawool Flannel Shirt - Deep Navy Deep Navy / XXL
Seawool shirt
Great fit and feel ( xxl ) and I’m 6ft 2 inches & 233lbs
What is your height? 6'1-6'3
What is your weight? 220-240
What size did you purchase? XXL
For what activity do you recommend this product? Casual Wear
Bruce A. j.
Verified Buyer
Rated 4 out of 5 stars
4 weeks ago
Reviewing
Men's Seawool Flannel Shirt - Sandstone Sandstone / L
Great
Soft and comfortable
What is your height? 6'1-6'3
What is your weight? 160-180
What size did you purchase? L
For what activity do you recommend this product? Casual Wear
Ryan O.
Verified Buyer
Rated 5 out of 5 stars
1 month ago
Reviewing
Men's Seawool Flannel Shirt - Deep Navy Deep Navy / M
Great shirt
Warm and comfortable
What is your height? 5'7-5'9
What is your weight? 120-140
What size did you purchase? M
For what activity do you recommend this product? Casual Wear, Travel, Work
For what activity do you recommend this product? Casual Wear
Jeffrey T.
Verified Buyer
Rated 5 out of 5 stars
1 month ago
Reviewing
Men's Seawool Flannel Shirt - Sandstone Sandstone / L
Flannel Shirt
Awesome fit and comfort. Love the color even in fall. So soft yet durable. Great gift for the holidays.
What is your height? 5'10-6'0
What is your weight? 160-180
What size did you purchase? L
For what activity do you recommend this product? Fishing
Loading...
Loading...
Recently Viewed
One Size Doesn't Fit All
All measurements are in inches and reflect body measurements. If you are in between sizes, size up for comfort.
Got questions? Email us at info@freeflyapparel.com.
Men
Women
Toddler
Youth
Alpha Sizes
Numeric Sizes
Chest
Waist
Hip
Sleeve
S
30–31
36–38
30–32
34–37
32–33
M
32–33
38–40
32–34
37–39
33–34
L
34–35
41–43
35–37
40–42
34–35
XL
36–38
44–46
38–40
43–45
35–36
XXL
40
47–49
41–43
46–48
36–37
3XL
50–52
44–46
49–51
36–37
Alpha Sizes
Numeric Sizes
Bust
Waist
Hip
XS
0–2
32–33
25–26
35–36
S
4–6
34–35
27–28
37–38
M
8–10
36–37
29–30
39–40
L
12–14
38 1/2–40
31 1/2–33
41 1/2–43
XL
16
41 1/2–43
34 1/2–36
44 1/2–46
XXL
44 1/2–46
37 1/2–39
47 1/2–49
US Size
Height (IN)
Weight (LB)
2T
33–37
27–31
4T
38–42
33–37
6T
45–49
44–48
US Size
Height (IN)
Weight (LB)
XS/6–7
45–48
45–50
S/8–9
49–52
51–65
M/10–12
53–57
66–80
L/13–14
68–62
81–95
XL/15–16
63–66
96–110
*Learn how to find your true waist below.
Please find inseam length on specific product detail page.