Long Sleeve Size Guide (Gildan 5400)
Long Sleeve Size Guide
Gildan 5400
Our long sleeve is the Gildan 5400, a sturdy 100% cotton knit with a classic unisex fit and ribbed cuffs. It runs true to size and sits straight through the body. Prefer a closer fit? Size down one. Want room to layer? Size up.
Size Chart
Measurements are in inches and refer to the garment laid flat. Width is measured pit-to-pit across one layer. Length runs from the highest point of the shoulder to the hem. Sleeve length is measured from the center back of the neck to the end of the cuff.
| Size | Width (pit-to-pit, flat) |
Length (shoulder to hem) |
Sleeve (center back to cuff) |
|---|---|---|---|
| S | 18.0" | 28.0" | 32.5" |
| M | 20.0" | 29.0" | 34.0" |
| L | 22.0" | 30.0" | 35.5" |
| XL | 24.0" | 31.0" | 37.0" |
| 2XL | 26.0" | 32.0" | 38.5" |
| 3XL | 28.0" | 33.0" | 38.5" |
Measurements may vary by up to an inch due to manufacturing tolerances, as each piece is made to order.
How to Measure
The easiest way to find your fit is to measure a long sleeve tee you already own and love, then compare it to the chart above.
Width: Lay the shirt flat and measure straight across from underarm to underarm, one layer only.
Length: Measure from the highest point of the shoulder straight down to the hem.
Sleeve: Measure from the center of the back neck, across the shoulder, and down the arm to the end of the cuff.
A Note on the Fit
This is a classic unisex cut, straight through the body rather than tapered. It runs true to size, so your usual size is a safe bet.
It is cut roomier than our women's Everyday Tee. If you prefer a closer fit through the waist, size down one. If you plan to layer it over a long sleeve or wear it loose, size up one.
One more thing worth knowing: this is 100% cotton, so expect a small amount of shrinkage in a hot wash. Cold water and a low tumble dry will keep the length where you want it.
Care
Machine wash cold, inside out, with like colors. Tumble dry low. Skip the bleach and the iron over the print.
Still not sure? Email us the armpit-to-armpit measurement of a shirt you love at hello@knownpack.com and we will tell you which size to order. Between sizes? We'll make it right, free.
Get Outside. Stay Present. Give Back.
The Known Pack
Our Mission
Leave the pavement behind. Find your wild.
Welcome to The Known Pack — a premium outdoor and nature-inspired apparel brand designed in Colorado, built for the people who believe the best moments in life happen when you finally get outside.
We create ultra-soft, garment-dyed Comfort Colors tees, vintage-washed fleece, and nature-inspired gear built around butterflies, wildflowers, botanical art, and the Rocky Mountain landscapes we love. Whether you're a backcountry hiker, a weekend camper, a gardener, or someone who just needs to slow down and breathe fresh air — The Known Pack was created to be the gear you reach for every time you head outside.
Our Story
Born Near the Foothills of the Rockies
Born near the foothills of the Rockies in Highlands Ranch, The Known Pack started with a simple belief: gear should do more than just look good. It should tell a story.
It should remind you of a wildflower meadow in full bloom. A cold morning at the trailhead. The sound of wind through the pines. A fresh start off the grid.
We wanted to create premium, broken-in apparel that feels like an old favorite from the very first wear — pieces that make you want to pack the car, roll the windows down, and see where the dirt road ends.
Wearable Art
For the Nature Lover
Our designs celebrate the natural world — swallowtail butterflies, wildflower fields, lavender, botanical illustrations, and the quiet beauty of the outdoors. These aren't just tees. They're wearable art for the woman who notices the butterflies, tends the garden, and finds peace in nature.
Every design is crafted with care, made to order just for you, and built to be worn for years.
Protecting Our Playgrounds
We don't just explore the wild — we protect it.
10% of every purchase goes directly to trail restoration and park conservation, helping keep the wild meadows, wildflowers, and open spaces we all love accessible for the next generation. When you wear The Known Pack, you're not just wearing something beautiful — you're helping protect the places that inspire it.
How We Give BackOur Promise
We'll See You Out There
We're here to create premium gear that makes you want to get outside. We care about delivering a flawless experience, backing our products with real support, and outfitting a community of people who share our love for the outdoors and the natural world.
Thank you for being part of the pack. We'll see you out there.
Max
Founder, The Known Pack
Find Your Wild
Explore the collection and find the piece that makes you want to get outside.
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