SRD:Fleet of Foot
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Fleet of Foot [General]
When running or charging, you can make a single direction change of 90 degrees or less. You can’t use this feat while wearing medium or heavy armor, or when carrying a medium or heavy load. If you are charging, you must move in a straight line for 10 feet after the turn to maintain the charge.
Without this feat, you can run or charge only in a straight line.