Härkila Heat Long Johns Willow Green/Black

Härkila Heat Long Johns are long underpants with sewn-in heating membranes. Power comes from a separately sold power bank, and they suit driven hunts, high seat hunting and outdoor use in cold weather.

The heating membranes are located in the lower back and just above the knees. The temperature is set to 35, 43 or 50 degrees Celsius with the button under the flap at the waist. The membranes are flexible, so the long johns can be folded and packed, and they can be machine washed.

The waistband holds a long, fabric-covered cord with a waterproof USB plug, so the power bank can be kept in a trouser pocket, for example. With a 10,000 mAh power bank they run at the highest 50 degree setting for about 7 hours at an outdoor temperature of 0 degrees. The membranes go into standby once the set temperature is reached and switch back on when it drops 1-2 degrees, so the heating regulates itself according to your activity level.

The fabric is 80% nylon and 20% elastane: quick-drying, stretchy and hardwearing. The cut is modern and fairly close-fitting, soft elastic webbing at the waist gives a comfortable fit and a dry bag is included.

Härkila Heat Long Johns - Features:

• Product type: Heated long johns
• Intended use: Driven hunts, high seat hunting and outdoor use in cold weather
• Heating: 3 heat panels (lower back and knees), 35/43/50 degrees Celsius, button under waist flap, automatic standby
• Power: External power bank via USB (not included); 10,000 mAh approx. 7 h at 50 degrees, 0 degrees outside
• Material: 80% nylon, 20% elastane; lining 100% polyester
• Fit: Modern fit, full stretch
• Details: Soft elastic webbing at waist, dry bag included
• Weight: 488 g
• Sizes: XS-4XL
• Color: Willow Green/Black
• Care: Machine wash in a mesh laundry bag, wash separately or with similar colors, do not bleach; do not use when wet, do not use pins; do not dispose of with household waste

An adjustable heated base layer for the legs and lower back.

Note: Power bank sold separately.

Product text updated 26.09.2026.