FlashGot is the free add-on for Firefox which downloads all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers. It supports almost all major download manager such as BitComet, Download Accelerator Plus,DownloadStudio, Free Download Manager,HiDownload,Internet Download Manager, JDownloader,Mass Downloader and Orbit for windows and Aria,Axel, cURL,FatRat,GNOME Gwget, KDE KGet,Uget for linux and Folx,iGetter,Leech, Speed Download for mac os x.
Firefox add-on page:
Download Flashgot from above links and restart your firefox.
To open Flashgot options,
Go to Tools menu in firefox and click Flashgot.