HDPE (High Density Polyethylene) Plastic Sheet 3/8 x 12 x 24 HDPE (High Density Polyethylene) Plastic Sheet 3/8″ x 12″ x 24″ Black lor. High density polyethylene (HDPE) is used in a variety of applications and industries where excellent impact resistance, high tensile strength, low moisture HENAN OKAYorption and chemical- and rrosion-resistance properties are required.