The Louisville Slugger Senior League Catalyst bat is made with the X-1 Composite design which uses 100 per cent aerospace grade graphite. The high strength fibers allow Louisville Slugger to use the best angle for performance while keeping the Catalysts barrel wall thin for maximum flexibility. A specially designed toughened epoxy resin is embedded in the graphite layers, locking the graphite layers together, forming a light, durable thin wall design.