I have taken a die apart before to see how it is made. The foam is glued on a wood base that holds the dies in place. The wood base is glued into the green plastic tray which is the housing for the die. The foam and wood base can be glued if they come lose if necessary with any all purpose glue. The foam is to protect the blades, make the die safe to handle, and give a surface for the fabric to stay in place.