of a distal portion of a probe assembly for a mapping catheter embodiments of the present subject matter use a body frame made of nickel titanium niti to provide shape memory other materials that possess an appropriate shape memory may be used because of the shape memory characteristic the distal portion of the catheter is flexible and can be straightened inside the sheath and can maintain its original shape when is out of the sheath according to various embodiments the loop section of the body frame is skived in the skived portion at least a portion of the body frame facing toward the interior of the loop is removed the skived structure allows the design to accommodate more space for the lead wires provides a small outside diameter profile provides balanced distal loop flexibility and provides a more controlled adjustable loop some embodiments taper the skived portion distally the tapered distal end promotes flexibility of the distal end of the loop portion which allows the mapping loop to be fed through the vascular more easily and to contract into a tighter loop in the tapered embodiments the amount of the body frame left at the proximal end of the skived portion is more than the amount of the body frame left at the distal end for example the.