characterised by an apertured layer, e.g. of expanded metal

Full Title

Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form > characterised by a discontinuous layer, i.e. apertured or formed of separate pieces of material > characterised by an apertured layer, e.g. of expanded metal