Patent ID: 7461424

Claim:
An apparatus, comprising: a case; and a plurality of polyurethane foam pieces disposed in the case, the plurality including a first plurality of foam pieces of a first average size, a second plurality of foam pieces of a second average size, and a third plurality of foam pieces of a third average size, with the first, second, and third average sizes being different, and with the first, second, and third pluralities of foam pieces disposed in the case in a mix, with the first plurality of foam pieces representing approximately 20 to 30 percent of the plurality of polyurethane foam pieces, and with the second plurality of foam pieces and the third plurality foam pieces constituting the remaining foam disposed in the case, in an approximately equal proportion by volume; wherein the plurality of a polyurethane foam pieces has a density of from about 1.8 pounds per cubic foot to about 1.9 pounds per cubic foot, and an indent force deflection at 25% of from about 27 to about 35.