This is the outer (metal) frame for the side window of your split window bus. You will need this to replace rusted out metal window surrounding or if you want to build more windows in your beloved kombi. A must when you want to go from a 11 window to a 13 of 15 window or if you wish to transform a 11 window kombi into a so much desired 21 window samba. You will need this metal piece to build in that extra needed pair of side windows.