"As mentioned in previous review, the fibre washer supplied is useless. Fortunately, having read previous reviews i was prepared with my pack of handy rubber washers and O rings. As soon as I fitted this valve, the fibre washer leaked. Replaced it with a 1/2 inch O ring and it's fine. Would have bought the competitor product, but the reviews were even worse. At least on this one it's only the washer that gets criticism!"