A training or safety aid for a baseball bat is disclosed. The device is configured to be placed on a bat, and indicators, which may be sound producing devices, produce a noise in accordance with selected qualities of the swing. In some embodiments, a flute-type opening is used, and may be configured with tubes to determine a pitch of a produced tone. An air scoop or funnel may be used with any of the devices that utilize airflow to produce a tone. Where more than one sound producing device is used, the devices are configured to only produce a sound within a narrow angular range of airflow, and are angularly spaced so as to produce sounds during different portions of a bat swing.