The more poles used, {HEAD ~ the greater the complexity} of {TAIL ~ the magnet} but the more uniform the magnetic field configuration 
of
The more poles used , { HEAD ~ the greater the complexity } of { TAIL ~ the magnet } but the more uniform the magnetic field configuration
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH