This product was designed to fill the empty cavity in a carton but add nothing to the weight of a carton, hence filling the carton to avoid movement or damage but not adding to the shipping costs.
The most common product is FLOPAK from Sealed Air; this is expanded polyethylene foam in a 3 dimensional figure 8, sold in 400lt bags. The product is fully recyclable.
A cheaper alternative is available in the form of chipped polystyrene foam off cuts, like the white foam around packed around electronic equipment when new.
Product Order Codes Commence with FP