| 摘要 |
<p>A drain ring of the type which lies under a water closet, and which has a tubular portion attached to the end of a drain pipe and a flange at the top which is held by bolts to the water closet, wherein the bolt-receiving regions of the flange are bowed-up to permit the reception of a bolt head under the flange by a workman positioned above the floor on which the water closet rests.</p> |
