Egg Crate

Egg Crate Rubber Midsole
The Egg crate pattern of square or diamond shape walls may fill the heel of a solid rubber boot sole. They save weight but allow for sturdy sole unit. Egg crate may also be used to replace foam inside the midsole of an inexpensive shoe. Egg crate may also be used to level the inside surface of a rubber outsole to allow sheet cut midsole to fit properly.

This is a rubber cuo sole with eggcrate inside