A superior system - There is nothing cheap about the look and feel of the X-Bolt rotary magazine. It's designed to be boringly reliable and endure the punishment that will break lookalikes from competitors. Original equipment quality and performance for all calibers. Features: Detachable rotary magazine constructed from a durable lightweight polymer Feeds cartridges directly in line with the bolt, instead of offset as with traditional leaf-spring magazines for a straight path right into the chamber Ergonomic magazine mounted release Standard caliber holds four cartridges