Joint Hop-up AEG 4UANTUM Friction Pro-High PerformanceDesigned to achieve ultimate consistency, the Friction Pro hop up bucking focuses on creating a perfectly centered axis of rotation with every shot. Although based on a traditional single point design, the unique contour of the contact zone generates enough friction to lift heavy balls up to 0. 48 grams, while minimizing the contact area to ensure there's no room for error. The result is a flat, consistent and precise trajectory!