Monument 4in. 100mm Green Air Bag Stopper - MON1292N

The chap who was blocking the 4" pipe for me, inserted the stopper and pressurised to 20psi. BANG. It burst. The reason was that the 4" pipe was inserted in a 6" pipe and the stopper was pushed into that area. So not a fault of the stopper in a way, but I would have thought the nylon bag would have contained the rubber bulb, even at a greater diameter than design.The chap contacted Monument, the manufacturer who have asked to see it - so they may replace it. Good service.Morale - check the drain diameters first! ;)John

This was a monumental failure. At less than one atmosphere it started leaking. Clearly a total waste of money and time and it is not the first time that Monument products have proved useless for the task they were intended to do. You would have thought I should have learned by now.