·Material: Unplasticized Ploy (Vinyl Chloride) Size: 63mm to 1000mm ·Ring Stiffness: SN4 and SN8 ·Color: cream or other colors upon request ·Standard: ISO 21138-2, ISO 21138-3, GB/T18477-1 ·Application: municipal sewage, rainwater discharge, flood waters drainage, irrigation, ventilation for mine and buildings, industrial waste discharge and communication protecting