Introducing Advanced Mountain Kit. The most sophisticated alpine climbing system The North Face has ever created. A specialist series, AMK incorporates apparel, accessories, and equipment. Collaborating with elite athletes, designers, and innovators, the collection redefines high mountain performance. Rethinking the needs of the world\'s best, Advanced Mountain Kit enables alpinists to push the limits of their potential.The AMK L3 Pullover is a 1000-fill RDS ProDown insulated midlayer. Lightweight and ultra-packable, it achieves the highest warmth-to-weight ratio. Boosting performance further, the L3 Pullover features TNF’s all-new 50/50 Down construction. Pairing air-permeable fabric with downproof baffles, it allows increased airflow during aerobic activity. An essential piece for stop-start alpine missions, extensive testing assures high-altitude performance.