Available in stores & online on July 25, 2017. From The North Face website:
"Tackle the challenges of rapid elevation gain and loss with this new, lightly insulated jacket that features our state-of-the-art Ventrix™ ventilation for balanced warmth and breathability. Perforations in key areas are designed to expand and dump heat or contract and retain as you move, so you won't overheat or sweat out."
Ventrix in Popular Mechanics' "Outdoor Retailer 2017: The Best New Gear of the Year":
Built for all-day adventures, the Ventrix's flexible insulation features small perforations that stretch open when you move to vent heat. When you stop to catch your breath, the perforations remain closed to keep you warm."
Via Feed The Habit, a cutaway image showing the Ventrix insulation:
"The North Face is taking things one step further by introducing Ventrix, which makes their active insulation even more breathable. They do this by cutting vertical slits into the insulation. When sitting still, these slits are essentially closed off, but when active, these slits open up to allow more moisture to escape. The design makes complete sense and should take their active insulation to another level of breathability. Ventrix will be available in the Summit L3 Ventrix Hoodie in fall 2017 which features 80g insulation combined with dynamic venting."
Described as: "A synthetic insulated mid layer that features a dynamic venting insulation layer that activates with movement and works in tandem with highly wind-permeable fabrics."