In one embodiment, {HEAD ~ the spacer} includes {TAIL ~ at least one cushioning segment} defining a gap for providing the separation 
includes
In one embodiment , { HEAD ~ the spacer } includes { TAIL ~ at least one cushioning segment } defining a gap for providing the separation
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH