As for stab set, movement you receive the stab needle and the stab needle which possess the needle hub which is locked to the basic end of the needle body and the needle body which possess ahead the sharp needle in the point possibly according to the longitudinal direction, you can provide ahead the needle in the point of stab needle unit and the housing and the housing which have the tubular casing which possesses opening which is projection possible, the casing is received by the applied part of the ring condition which installation and removal unrestrictedly is installed and inside the housing inside, the plunger which possesses the connected section which is connected with the needle hub installation when the casing has been installed in the applied partIt possesses with the stab device which it has, extends the casing, to the peripheral section, it possesses the plural casing side convex sections which are arranged according to lap the direction of the peripheral section extends the applied part, to the inside perimeter section, it possesses the plural applied part side convex sections which are arranged according to lap the direction of the inside perimeter section, in installation state, one applied part side convex section is located at least between the casing side convex sections which are adjacent.穿刺セットは、先端に鋭利な針先を有する針体と針体の基端部に固定された針ハブとを有する穿刺針と、穿刺針をその長手方向に沿って移動可能に収納し、針先が突出可能な開口を有する筒状のケーシングとを備える穿刺針ユニットと、ハウジングと、ハウジングの先端部に設けられ、ケーシングが内側に着脱自在に装着されるリング状の装着部と、ハウジング内に収納され、ケーシングが装着部に装着された装着状態で針ハブと連結する連結部を有するプランジャとを備える穿刺装置とを有し、ケーシングは、その外周部に突出し、外周部の周方向に沿って配置された複数のケーシング側凸部を有し、装着部は、その内周部に突出し、内周部の周方向に沿って配置された複数の装着部側凸部を有し、装着状態では、隣り合うケーシング側凸部の間に少なくとも1つの装着部側凸部が位置する。
