Lightweight Next-to-Skin Performance
Build your day on a solid foundation with the Primus K1 Pullover baselayer. Wool balanced with synthetic fibers delivers long-lasting durability, easy wash cycles, and the fast moisture transport your layering system needs. Flat seams ensure bulk-free layering, and thumbhole cuffs combine with a ½-zip front to offer adjustable warmth.
Our wool combines with synthetic fibers to create the ideal performance fusion for moisture management: wicking up and lifting out sweat, protecting against odors and wash shrinkage, increasing durability, and ensuring next-to-skin comfort. Your system’s moisture transport starts here.
Flat-seam construction ensures all-day comfort, delivering a smooth next-to-skin feel and reducing bulk when layering up.
Thumbhole cuffs extend coverage for warmer hands, and a 1/2 zip front helps shed extra heat in a hurry.
K1 - PRIMUS
WHEN TO USE
Below 50° F as a next-to-skin baselayer.
PAIRS GREAT WITH
Active insulation and softshells.
BENEFIT OVER OTHER LAYERS
Highly breathable, fast-drying layer that can have any other layer worn over it.
Learn more about layering:VIEW SYSTEM BUILDER
Body Material2.7 oz. piqué 78% polyester/27% wool
Weight (Size L)8.5 oz.
Trade Agreements Act Compliant
Designed in Seattle. Imported.
Great base layer shirt
Perfect as a base, great to keep in the bag and and make part of your sleep system.
Fit was right on. Quality garment.
Awesome and well made. Very impressed with the form and function of the Primus K1 pullover and all Beyond items I have purchased thus far. Great company with fast shipping. Can't recommend enough.
Got it on sale, the size was a little smaller than advertised but a simple size up made it work. Excellent service for the replacement and wasn't punished for the sale-purchase mistake. Good garment, not much else to say, layers well and keeps me warm even in situations where other clothing fails.
Need Help? Contact us with any size or fit questions. 206-767-0307
Primus K1 Pullover
Height 5' 8" - 6' 2"
Short: -2 Inches in Sleeve and Torso
Long: +2 Inches in Sleeve and Torso
Chest Widest part of chest
Sleeve Center back of neck to shoulder seam to sleeve hem edge
Standard True to Size | Active Layering
Expedition Oversized | Static Layering