A charged particle optical system comprising a beamlet generator for generating a plurality of beamlets of charged particles and an electrostatic deflector for deflecting the beamlets. The device is characterized by the structure including platform having a foot base plate rotatably mounted thereon for the golf’s rear foot, wherein the foot base plate is adjustable in two planes. As a result of the flexible material, the jacket allows unimpeded diastolic filling of the heart. A lancet body has a smoothly curved wave contour with at least one crest and at least one trough for engagement with a cooperating receiver of a lancing device.