PART NO.  SPL.PAGE  DESCRIPTION                                                            
AFH1753   15.R.10   Sealing rubber for boot lid -(boot lid, Tourer, 1500)
AFH1753   16.R.10   Rubber -boot lid sealing -(boot lid fittings, 1600 and 1600-MK-II)
AFH1753   TS.R.9    Rubber -boot lid sealing -(boot, Twin Cam)

When done properly, this is a nice soft hollow extruded part with closed cell foam rubber to be water proof (not absorbent).

For more information, see BD-116A