2.Foam: we all use high density foam(D40-45 for cushions and D30 for back and armrest), we never use recycle foam for any part of sofa.
3.Cover material: all cover material selected pass the relative test like rub test, color fastness test. Tremendous options including cotton,linen and synthetic material.
4.Others: we use no-sag sinuous spring and wooden legs for the modern sofa.