Jonbuoy Recovery Module Mark 5 - white case. Recovering a man overboard can be an extremelyhazardous operation for both the crew and the person being recovered - regardless of the vessel size. TheJonbuoy Recovery Module is designed to make this a simple operation, while increasing vital visibility andbuoyancy for the casualty. Accepted as a direct replacement for a traditional danbuoy, horseshoe, drogue,light and whistle, specified within the ISAF offshore special regulations.