the CoreCork constructio starts withj 30kg/m3 recyclet EPS core, wrapped in basalt or carbon fibres and a 3mm CoreCork sheet.   The outside glas is made of premium Hexcel 1522 fibres. The epoxy used has 35% of it's molecular structure deriving from plant origin. All this gives you a very soft/comfortable  but still very solid board that not only looks great , it's also more sustainable than most other constructions.