Sealing for medical devices/instruments

A catheter including a proximal section, a distal end and a lumen extending along a length of the catheter from the proximal section to the distal end, the proximal section of the catheter comprising:

• a proximal terminal end defining a perimeter of a proximal opening of the lumen;
• and
• a relatively soft part extending distally from the proximal opening of the lumen to a main portion of the lumen, the main portion extending distally to the distal end of the catheter;
• wherein the relatively soft part includes a distal face, adjacent to the main portion of the lumen, a slit and a bore, the bore including a proximal opening, a distal terminal end and a funnel-like segment that extends between the proximal opening and the distal terminal end of the bore and tapers down in size from a proximal diameter thereof to a distal diameter thereof, the distal terminal end of the bore being proximally offset from the distal face of the part, and the slit extending proximally through the part, from the distal face thereof and into the funnel-like segment, the slit having a size, or radial extent, that is greater than the distal diameter of the funnel-like segment of the bore;
• the slit and the bore of the relatively soft part form a seal zone portion of the lumen;
• and
• the soft part further forms only a portion of the perimeter of the proximal opening of the lumen.