A sterile tubular plastic sheath designed to be percutaneously placed into a natural body space (e.g., vein, artery, ventricle, peritoneal cavity), or an artificial passageway (e.g., created by means of a catheter tunneller), and through which a catheter is subsequently inserted (by pushing) for placement. It typically has a handle (e.g., T-shaped wing grips) at the proximal end, and may have radiopaque graduated markings at the working end to make it visible on x-ray. This is a single-use device.