Metolius Bomb Shelter Single Portaledge Red One Size. The strongest, most durable portal edge available. Innovative spreader bar keeps the frame rigid and the bed tight. (1-1/8" / 28.5 mm) aircraft-quality 6061-T6 tubing for maximum strength and rigidity. CNC milled corner fittings for maximum strength, light weight and easy set-up. Anodized poles and corner fittings keep the parts from galling and sticking for easy set-up, corrosion resistance and durability.