Atomic Pro S1 Junior - The lightweight Atomic Pro S1 Junior is a durable skate ski that's ideal for those just starting out in skiing. We gave the ski a wide sidecut that significantly improves balance, and a light, stable and robust Densolite 100 core that makes it easy to get started in cross-country skiing. The Pro S1 Junior JR is the perfect ski for young cross-country skiers who want to progress.