SPECIFICATION MET: 
A-A-59136 Class 1, Grade A, Type I, Polyethylene Foam Plank Material.
This was formerly PPP-C-1752.
Grade A - Standard (The color shall be white).
Class 1 - General purpose polyethylene plank material (unskived).
Type I - 14 Kg Constant Compression Creep, See 3.10
Country of Origin: United States (USA).