I purchased them thinking they snapped on the trays. They were designed just to sit on top so the trays could be stacked. They did not work for what I needed so I returned them.
Great for organizing centers.
June 15, 2010
From Rhode Island
Setting Child Care Center
We bought these trays to organize our shelves in our manipulative center to get rid of our big bins. They allow the children to choose an activity easily and see all that is available to them, without clutter and digging.