... product line is spa cover ,outdoor spa cover, hot tub cover ,bathtub cover, swim spa cover, swimming pool cover ,lifter for cover ,PVC water pipe ... Marine Grade top vinyl.and 100% high density insulation foam.3) Competitive price: we are one of the largest ... foam is vacuum sealed4) Gauge Aluminum C-Channel: Lighter, extra strength and corrosion proof, ensuring structural integrity for the life of cover ...