"I cannot believe how protective this jacket is. Without being incredibly heavy or stuffy, it keeps all wet weather out." —Gearhead® Expert SammyBy teaming up with Pertex to create a lightweight, breathable, and totally waterproof shell, we hit the nail on the head, creating the perfect summer rain jacket. The Backcountry Runoff 2. 5L Rain Parka's loose-fitting urban silhouette layers comfortably for warm-weather precip defense.