{HEAD ~ Each disk} is positioned tangent to {TAIL ~ the surface} of an AGA chip in a specific orientation 
{ HEAD ~ Each disk } is positioned tangent to { TAIL ~ the surface } of an AGA chip in a specific orientation
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH