2.5" risers to stack 2 lacks a little higher to clear my printer.
Also brackets for mounting the the panels you plan to use... wood, acrylic, corrugated plastic etc. You can attach the panels with hardware by drilling the brackets or just use silicone sealant to adhere the panels.

Screw holes made for bulldog brand #8 wood screws available from Walmart. I am using 3/4" length screws use a 1/8" drill bit to pre-drill the holes in the table legs so you don't spit the particleboard.