A fluid transfer system comprising: a container comprising: a container body having a sidewall extending between an open top end and a bottom end along a central axis to define an interior cavity ; and at least one protrusion aligned with the central axis and extending from an interior portion of the sidewall into the interior cavity ; and a connector configured for receipt within the interior cavity , the connector comprising: a body having a distal end , a proximal end , and a sidewall extending between the distal end and the proximal end and defining a fluid passageway therethrough; an inner member provided at one of the distal end and the proximal end of the body ; an outer member surrounding at least a portion of the inner member , the inner member configured to rotate freely relative to the outer member ; and a locking arrangement provided on at least a portion of the inner member , wherein the locking arrangement is configured for cooperating with the at least one protrusion to prevent rotation of the inner member relative to the outer member , characterized in that the locking arrangement is accessible through at least a portion of the outer member . a container comprising: a container body having a sidewall extending between an open top end and a bottom end along a central axis to define an interior cavity ; and at least one protrusion aligned with the central axis and extending from an interior portion of the sidewall into the interior cavity ; and a container body having a sidewall extending between an open top end and a bottom end along a central axis to define an interior cavity ; and at least one protrusion aligned with the central axis and extending from an interior portion of the sidewall into the interior cavity ; and a connector configured for receipt within the interior cavity , the connector comprising: a body having a distal end , a proximal end , and a sidewall extending between the distal end and the proximal end and defining a fluid passageway therethrough; an inner member provided at one of the distal end and the proximal end of the body ; an outer member surrounding at least a portion of the inner member , the inner member configured to rotate freely relative to the outer member ; and a locking arrangement provided on at least a portion of the inner member , wherein the locking arrangement is configured for cooperating with the at least one protrusion to prevent rotation of the inner member relative to the outer member , characterized in that the locking arrangement is accessible through at least a portion of the outer member . a body having a distal end , a proximal end , and a sidewall extending between the distal end and the proximal end and defining a fluid passageway therethrough; an inner member provided at one of the distal end and the proximal end of the body ; an outer member surrounding at least a portion of the inner member , the inner member configured to rotate freely relative to the outer member ; and a locking arrangement provided on at least a portion of the inner member , wherein the locking arrangement is configured for cooperating with the at least one protrusion to prevent rotation of the inner member relative to the outer member , characterized in that the locking arrangement is accessible through at least a portion of the outer member . <EOS>