A medical retrieval device and method used in endoscopic procedures to retrieve stones has a shaft comprising a sheath with a lumen and a drive wire slidably disposed within the lumen for operating a stone entrapping mechanism on the distal end of the retrieval device. The shaft, sheath and drive wire each have proximal, intermediate and distal portions, and each of the corresponding portions are in generally similar locations along the longitudinal length of the device. The stone entrapping mechanism is constructed of a plurality of flexible elements that are outwardly disposed to form an entrapment space and having an open and closed configuration. Configuration of the flexible elements and the entrapment space vary within the stone entrapment mechanism.