These top quality, light-weight 11/16" thick boards are a must for every draftsman and engineer. The drawing surfaces are 2-ply basswood, permanently attached to a honeycomb core, which gives these boards excellent strength yet keeps them light-weight. The Feather-Weight drawing board has solid basswood edges that are straight, smooth and parallel. The Metal-Edge drawing board has specially machined, triple-groove, metal-edges along the short side, assuring a permanent, true square edge.