Next Spring, The North Face (TNF) will debut the Flight Trinity designed to tackle long distances on technical trails in all conditions, as tested by TNF’s pro runners including Hillary Allen, Dylan Bowman and Zach Miller. We recently got our feet in a pair and, from what we can tell from initial test miles, both the outsole and the guts deliver a comfortable, fun ride.

We tested the Flight Trinity on a range of surfaces, and it tackled muddy trails, slick roots, soggy leaves, and dry, loose rock with ease. The outsole design, called EXTS (short for Exploration Trax System), is a proprietary, patent-pending combo of renewable rubber compounds, a unique lug shape, and purposeful tread orientation. Its composition includes 40 percent plant-based (and therefore renewable) rubber. With this natural rubber comes softness, which the brand says allows for improved traction on uneven surfaces.

TNF tinkered with ingredients until it found the right blend for grip in wet and dry conditions, as well as for durability. From the biomechanics lab and athletes’ wear testing, the brand gathered feedback that helped determine where exactly to put “stickier” rubber.

The tread consists of three-prong lugs, like the inside of a peace symbol, and triangle-shaped lugs. It’s designed to shed trail debris and also facilitate a smooth heel-to-toe transition. Along the sole, the lugs are angled for optimal braking and acceleration (going fast when you want to).

On steep-ish Pacific Northwest trails, this concept held up. The shoes felt great underfoot during pick-ups and let loose on downhills. They even handled a few on-road and sidewalk miles with ease.

At a surprising 8 ounces (women’s size 7), the Flight Trinity is pleasantly bomber. With a stack height of 20mm in the heel and 12mm in the forefoot, copious EVA cushion forms a wide, stable base (all the better for tackling long distances) but doesn’t compromise responsiveness. Initially, it felt like a lot of shoe, but on the trail, that thought vanished. Step-in comfort, many thanks to a high-rebounding OrthoLite insert, was solid.

On top of the shoe, a two-layer upper fights against the elements. A ripstop textile, on top of a sock-like knit bootie, creased noticeably at the base of the toes (which could aggravate skin after a few hours). This construction bagged out a bit through the midfoot, but tightening the round laces seemed to help with a more secure fit. The shoe also has a 3D-printed heel counter for a nice lock-down and a light toe cap plus tread that wraps in front of the toes for protection.

The Flight Trinity will be available in February 2019 and will be priced at $140.