Outstanding flexibility and simple installation. Long endurance due to high strength against pressure. No light penetration and, therefore, no moss or microorganism. Manufactured by special method, the colors are different in inner and outer layer. Inner diameter: 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8 inch Working pressure : 7~3kgf/cm2 Bursting pressure : 22~9kgf/cm2...