Lightweight Next-to-Skin Performance
Build your day on a solid foundation with the K1 - Primus Long John baselayer. Wool balanced with synthetic fibers delivers long-lasting durability, simple wash cycles, and the fast moisture transport your layering system needs. Flat seams ensure bulk-free layering, and a specialized fly provides support and fuss-free access (even with gloves).
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.
The Ballhalla™ fly keeps you comfortable all day long with anatomical support and minimal bulk, and the unique design ensures easy access even while wearing gloves.
Flat-seam construction ensures all-day comfort, delivering a smooth next-to-skin feel and reducing bulk when layering up.
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)7.1 oz.
Trade Agreements Act Compliant
Designed in Seattle. Imported.
The K1 Primus long john and shirt are both very comfortable. I have a hard time not wearing them. I wear them around the house as pajamas and they keep me a little warmer when out on a cold day and they feel comfortable while sweating in them on a hot day. I feel they are the ideal weight for a lightweight baselayer.
Issues: Originally ordered small regular, because that seemed to make sense with the sizing chart (I usually wear 30 waist 32 length pants) but they were way too short, halfway up my calves I believe. They did a good job with a size exchange though and the small-longs fit great. Another issue is that the fabric pills pretty quickly on the outer surface. However, it still feels comfortable. Some fabrics become a bit irritating when they pill too much. These would of course be more comfortable without it but it is still beyond anything else I have as far as comfort in a variety of environments.
Nice fit and keep me warm!
The LS shirt is bit too tight in medium size when usually medium would fit just right for me. Otherwise it’s very good and better for winter and fall.
Good fit, not really cold enough yet, but purchased as a spare, so like the first, will do it job.
Exactly what I needed out of a warm base layer. M its very close to the skin on a 5'10" 190lb "athletic" body.
Need Help? Contact us with any size or fit questions. 206-767-0307
K1 - Primus Long John
Height 5' 8" - 6' 2"
Short: -2 Inches Inseam
Long: +2 Inches Inseam
Waist Preferred Pant Waist
Hip 7" Below Preferred Waist
Inseam Regular Crotch to floor
Standard True to Size | Active Layering
Expedition Oversized | Static Layering