If you have previously recommended this thread, you should see a tick / check mark on the recommend button. Click the tick to undo the recommendation (the tick may appear to change to a cross as you do this.) If you added a comment with your recommendation, you will need to delete that from your facebook wall separately.
Mine is a Wesco pushboy but I am sure there are other brands like it. The rounded full-height top part completely lifts off to reveal a metal bucket on wheels underneath which is where you put the bin bag - the prob I am having is cleaning inside the actual head which lifts out (or keeping it clean). Basically, the flappy thing is not really very big so inevitably, rubbish makes contact with the inner head on its way down despite ultimately falling into the bag at the bottom - it is easy to clean the bottom - its the top part of the top bit I am worried about (confusing, I apologise)