In {HEAD ~ an advantageous form} of construction, the dial has at least one magnet, which by rotation of the dial is guidable along the sensors realized in {TAIL ~ the form} of field probes 
In { HEAD ~ an advantageous form } of construction , the dial has at least one magnet , which by rotation of the dial is guidable along the sensors realized in { TAIL ~ the form } of field probes
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH