A piezoelectric single pole single throw (SPST) switch has been developed, since there is no satisfying commercial low resistance, high current DC contact RF switch available which is operable at 4.2 K and in a high magnetic field of at least 0.5 T. This piezoelectric switch shows very low insertion loss of less than -0.1 dB within a bandwidth of 100 MHz when operated at 4.2 K. The switch could also be used to mechanically disconnect and connect electrodes or electrical circuits from one another. (C) 2013 Elsevier B.V. All rights reserved.