A steerable ground piercing tool includes an elongated outer housing having a lengthwise extending bore and an inner assembly at least in part disposed within the outer housing. The filter element collapses into the outer end of a catheter for deployment and retrieval through a vascular system of a patient. The inner side surface includes: a perpendicular surface standing upright from the inner end of the seal surface in parallel with the outer side surface; and a conical surface inclined toward the outer side surface extending outward in a radial direction from an outer peripheral end of the perpendicular surface. A plurality of local source line decoder circuits corresponding to the row banks are provided for decoding a selected source line segment based on the column address as well as a Bank Select signal generated from the row address of a particular cell. The roller cutter profile may extend beyond the fixed cutter profile in the shoulder and gage sections, possibly with the fixed cutter profile extending beyond the roller cutter profile in the nose section andor a cone section. Smooth and easy movement of the pullout storage structure is facilitated by an over-center assist member.