A tissue graft product includes at least one collagen layer comprised of submucosa or renal capsule tissue having slits therein to provide a mesh pattern which in turn establishes a graft structure that is highly deformable. The slits and mesh pattern provide for improved characteristics when utilized as a tissue graft and in particular an external wound care. Preferred devices have multiple submucosa, renal capsule or other collagenous extracellular matrix layers, providing a substantial and lasting scaffold for tissue ingrowth during wound treatment.