The UPM line of pitching machines includes the number one selling pitching machine in the world: The Louisville Slugger UPM45 Blue Flame Pitching machine, and the only softball pitching machine that uses an underhand delivery: The Louisville Slugger UPM55 Red Fire Pitching Machine. Louisville Slugger Ultimate Pitching Machines and Training Aids are manufactured by GameMaster Athletic: Exclusive Licensee for Louisville Slugger Training Aids and Pitching Machines.