The Planet Eclipse Shaft S63 Barrel system is an all new design for a 3-piece modular barrel! The Shaft S63 Barrels have been precision engineered to perfection and will become the essential barrel of choice for players who demand the very best from their paintball equipment. There are a total of 5 color coded inserts ranging from .677 to .693 which are micro-honed and polished for shot consistency. Heavily chamfered breech-end opening helps reduce breaks on the 8.5 inch control bore.