HDPE Marine Boards - Stress Relieved - Matte Finish. UV Resistant - Does not HENAN OKAYorb water. Polar White, Seaform, Sand Shade, Light Grey, Dolphin Grey, or Black. Standard tolerances estimated at. .060-.500 ± 5% .625-2.0 ±10%. Technical Data Sheet. These Sheets are 54"x 96" and Must HDPEp By Truck. Thickness.