Outdoor Vitals Highline Thermal Leggings

The Highline Thermal Leggings are an ultralight fleece base layer for the cold hours of a mountain trip: frosty starts, windy breaks above tree line, and long nights in camp. A size Small weighs 3.5 oz, so they earn a spot in the pack even on trips where you hope you won’t need them.

How warm are they?
The fabric is a proprietary 102 g/m² polyester fleece from Toray, brushed on the inside to trap warm air and left smooth on the outside to hold up to wear under pants. They are a light base layer, not an insulated pant. Under hiking pants or inside your sleep system, they add real warmth for very little weight. One customer wore them through eight days of freezing weather with a low of 14°F. On the coldest trips, plan to layer insulated pants over them.

Why no spandex?
Highline is 100% polyester with 0% spandex. Stretch and shape retention come from the knit itself, which keeps the weight down and helps them dry faster after a sweaty climb or a damp night.

Will they overheat on the climb?
A gusseted mesh crotch panel vents heat where it builds and moves with you on high steps.

What are they built for?
Worn under shorts or pants on the trail, or on their own for sleeping and around camp. They are not built to be rugged standalone pants for bushwhacking or rock. There is no fly and no pockets. That is a deliberate tradeoff: every ounce has to earn its place.

How do they fit?
Sizes XS to 3XL. Inseam is 30" in size Medium and changes 1 inch per size. Check the size chart before your trip, since used gear cannot be returned.

Specs
Weight: 3.5 oz (size S)
Fabric: Toray proprietary polyester fleece, 102 g/m², brushed interior
Vent panel: jersey knit mesh, gusseted crotch
Spandex: 0%
Inseam: 30" (size M), changes 1" per size
Color: Black