Posted by Bruce Beveridge on September 28, 1999 at 02:58:14 in 199.179.170.203 :
Many of you may have noticed those port holes with the four tabs on them, vertical and horizontal. I just received a good picture of these and they are adjustable pads on screw shafts. They must be spacers of some form that secure the glass. Each tab had one of these screws in them. the pad faces the glass.
Bruce