The stand has {HEAD ~ a planar base} mounted on {TAIL ~ surface engaging members} such as steerable casters 
The stand has { HEAD ~ a planar base } mounted on { TAIL ~ surface engaging members } such as steerable casters
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH