Balsa in the special grade up to 130 g/dm3 sits between the lightest boards and ordinary stock. At a density of no more than one hundred and thirty grams per cubic decimetre it is still light, yet the surface is noticeably firmer, so it dents less and holds its dimension better under handling.
That makes it the grade for ribs, formers and load-bearing areas of sheeting, and for anything where the lightest class would simply be too soft to trust.
