In one aspects of the present invention, an induction resistivity tool incorporated into a downhole tool string comprises a downhole tool string component comprising a mid-body intermediate first and second tool joints adapted for connection to adjacent tool string components. The mid-body comprises a central bore formed within a tubular wall of the component, the tubular wall comprising an inner and outer diameter. At least one annular radial recess is formed in the outer diameter of the mid-body and comprises a coil adapted to transceive induction signals outwardly from the mid-body, and at least one flexible ring of magnetically conducting material is disposed intermediate the coil and a surface of the recess and arranged within the annular radial recess such that it filters a range of frequencies of the induction signals.