Back-up boards, back-up sheets, back-up panels, entry boards, entry sheets, and entry panels made out of epoxy resins for use in the operation of drilling holes in printed circuit boards; Back-up boards, back-up sheets, back-up panels, entry boards, entry sheets, and entry panels made out of fiber board for use in the operation of drilling holes in printed circuit boards; Back-up boards, back-up sheets, back-up panels, entry boards, entry sheets, and entry panels made out of wood for use in t...