In order to convert MOV to FLV video, you must have FLV Converter for Mac OS X. After that you can follow the user guide to convert the video. However, if you want fastest video conversion then you will need to configure some conversion settings such as frame size, frame rate, audio codec, bit rate etc. After adjusting these settings, you can achieve fastest mov to flv conversion. For more details see https://flvconvertermacosx.com