? Buying guide: 50mm, 75mm, 110mm, and 160mm are the diameters of the water pipe. You can measure the circumference of the water pipe. The insulation cotton of 20 cm 28 cm 38 cm 56 cm width is the circumference of the water pipe.? Scope of application: Insulation cotton is widely used to better protect outdoor pipelines from freezing, car noise insulation, roof insulation and better use in industrial and construction industries. ? Scratch resistant. The surface high-fiber cloth is fiberglass,aluminum foil layer, Heatproof, Block transmit sunlight, Wear-resistant and scratch-resistant surface. ? Insulation cotton has good waterproof performance, waterproof and moisture proof, no mold, corrosion resistance, surface flame retardant material, fireproof, flame retardant, and higher safety factor . ? Thickened high-density insulation layer, closed-cell foaming, uniform foaming, high elasticity, good sound insulation and warmth,strong adhesive backing, self-adhesive sealing, easy to use and install . ? Buying guide: 50mm, 75mm, 110mm, and 160mm are the diameters of the water pipe. You can measure the circumference of the water pipe. The insulation cotton of 20 cm 28 cm 38 cm 56 cm width is the circumference of the water pipe.