6" (150mm) PVC Drain Bag. Used when testing or during maintenance on drainage / sewer work. Easily inflates using standard air pump with fitted schrader valve (as vehicle tyres etc..). To create an air tight seal in pipes for a back pressure of 4"/100mm U Gauge, as requested by British Standards. Easily inflated for trouble free pipe sealing. Ideal for use in areas where access is smaller than the test diameter. 1.2m Fitted Hose.