The remaining needle insertion of the utility model is formed with hole sells, has the insertion stop for utilizing the cylindric insertion section formed with the Rockwell hardness of ISO2039-2 regulation for the resin in the range of R60 ~ R120 and the cardinal extremity that the what insertion section is set, what the front end for more than front end of above-mentioned insertion section stating insertion section reached vascular wall or vascular wall most nearby part but does not reach intravascular state and the mode of indwelling has the shape of band circular arc, the above-mentioned insertion stop of what is provided with maintaining part of at least one recess portion as operation when.本新型之留置針插入用孔形成銷，具備利用以ISO2039-2規定之洛氏硬度為R60~R120之範圍內之樹脂而形成之圓柱狀之插入部、及設置於該插入部之基端之插入停止部，上述插入部之前端以上述插入部之前端到達血管壁或血管壁之最近處之部分、但未到達血管內之狀態而留置之方式具有帶圓弧之形狀，於上述插入停止部，設置有至少一個凹部作為操作時之保持部。
