DetailsMarmot Men's Size Chart At less than 5 ounces, the Bantamweight Jacket is the lightest fully featured rain jacket Marmot has ever made. This athletic-fitting, ultra-lightweight jacket offers true outdoor athletes the extreme rain performance they need to stow and go as they head up mountain—without the hassle of extra weight in their pack. Waterproof, windproof, and lightweight Pertex® Shield fabric with stretch is paired with a durable water-repellent (DWR) finish for the ultimate in rain protection and breathability. Essential features like ultra-lightweight, ventilating underarm laser-drilled holes, seam-taping, internal and external pockets, and an adjustable hood and hem create a customized fit. It all stuffs into an internal pocket for the ultimate streamlined outdoor experience.