A system and method are disclosed for deploying an elongated unit in a body cavity, for introducing an interchangeable tool to a slender shaft having a distal end. The system comprising: an elongated unit comprising a longitudinal axis and a distal portion arranged to protrude through a first port into the body cavity. At least one maneuvering unit connected to the elongated unit for maneuvering the distal portion of the elongated unit in a 3D coordinate system to a determined depth and orientation in the body cavity. The at least one maneuvering unit is arranged to selectively deploy the distal portion of the elongated unit at the determined depth and orientation at a distance with respect to the distal end of the slender shaft and selectively align the longitudinal axis thereof with a longitudinal axis of the slender shaft. The elongated unit and/or the slender shaft is arranged advanceable relative each other, such that once the distal portion of the elongated unit is deployed the distal portion of the elongated unit reaches and/or captures the distal end of the slender shaft.