1/4 inch anti-uv high density plastic board export Marine Board & Sea Board Plastics Okay. HDPE has a large strength to density ratio of about 0.93 to 0.97 gra. HDPE plastic has easy to machine and mold which makes the engineering process run smoothly. (High Density Polyethylene) Plastic Sheet 1/4" x 8" x 12” Black lor 4.2 out of 5 ...