main material are pure WOOD PULP and Acrylic resine, not cured , mainly apply to construction machines such as navvys , mineral machine , such off road vehicles, the filter area is 0.55-1.2 ㎡, weight is 135g/㎡, thickness is 0.54mm, air permeability (△P200Pa)is 500 L/㎡*s, the max pore size is 90 μm, resent content is 22%.