PROBLEM TO BE SOLVED: To provide a tubular member which permits a difference in grade to be easily confirmed.SOLUTION: The tubular member 1a receives a smaller diameter ring member fitted into the tip side inside periphery. The member has a fitting portion 2 on the inside periphery and grants a visually recognizable shape 4 to the fitting portion 2.COPYRIGHT: (C)2011,JPO&INPIT【課題】等級の異同を容易に確認することができる管状部材を提供する。【解決手段】管状部材1aは、先端側の内周面に、より小径の環状部材が嵌合される。該内周面に嵌合部2を備えると共に、嵌合部2に視覚により識別可能な形状4を付与する。【選択図】 図1