multiple first portions 22 and multiple second portions 24 connected in a line along respective electrodes 18 a 18 b as shown in fig1 and 3 according to an embodiment around a first portion 22 122 the respective two immediately adjacent electrodes e g 18 a 118 a and 18 b 118 b are substantially parallel to one another the inclusion of recess portions 29 does not affect the parallel position between electrodes 18 a and 18 b fig1 and 3 show that electrodes 18 a 118 a and 18 b 118 b are substantially parallel to one another throughout the y axis which is a specific embodiment the scope of the invention is not limited by the configuration shown in fig1 and 3 according to an embodiment two immediately adjacent electrodes 18 that are separated by separation portion 20 e g 18 a and 18 b are connected to different polarities illustrated by u201c u201d and u201c u2212 u201d in fig1 and 3 of a voltage source not shown as a consequence when a clamping voltage is applied to electrodes 18 a and 18 b an electrical field adjacent to embossment 16 will be created which is substantially parallel to surface 14 of body 12 any type of clamping voltage may be used and all are included in the invention for example the clamping voltage may be one of a direct current dc and an alternating current ac preferably according to an embodiment a bipolar square wave voltage having a peak to peak amplitude of at least 1000 volts and a frequency in the range of approximately 30 hz to approximately 300 hz may be used as the clamping voltage as such the u201c u201d and u201c u2212 u201d used in fig1 and 3 do not limit any.