Proven performance, excellent range, and superior accuracy, the perfect bucking for 350-400 FPS. The easiest way to instantly improve your performance. Over a decade of engineering prowess, superb quality, and tolerances, you can count on a Prometheus bucking to hop your BBs even further and more accurately.   MAINTENANCE: For best maintenance, please replace your bucking every 20,000 rounds, or when accuracy and performance begin to become extremely inconsistent. Use silicone spray lightly on the exterior of the bucking for easier installation. Be careful not to get any oil, silicone, or grease on the inside of the bucking or barrel as it may affect performance.   FEATURES: ・Designed for 350-400 FPS ・Use 0.28-0.32g BBs for best performance ・Combine with a Prometheus Barrel and Hop Up Chamber for maximum effect.