Sealing valve

A sealing valve, comprising:

• a main tubular body extending longitudinally between a proximal end and
• a distal end, comprising:
• a proximal segment extending distally from the proximal end;
• and
• a tapering segment extending from the proximal segment and tapering radially inward in the distal direction;
• a membrane valve portion extending around and radially away from the main tubular body, comprising:
• a membrane juncture, along which the membrane valve portion is attached to the main tubular body;
• a membrane body, extending radially away from the membrane juncture;
• and
• a membrane lip:
• wherein the membrane valve portion is resiliently biased toward the proximal direction, and is configured such that the membrane valve portion bends distally when flow-induced pressure gradient is applied thereto by fluid flowing in the distal direction;
• wherein the distal end is configured such that the distal end transitions between a distal free state, when no tube extends there-through, and a distal sealed state, when a tube extends there-through, sealing against the tube while no flow-induced pressure gradient is applied thereto;
• and
• wherein the distal end is made of a resilient flexible material, configured such that the distal end expands in the radial direction away from the tube extending there-through, when fluid pressure is applied to the distal end by distally-oriented fluid flow through the main body.