There are two models of one-way degassing valves for traditional coffee bags: convex (built-in) and concave (explicit). This product design focuses on re-designing the whole valve structure. The holes on the porous filters of traditional one-way degassing valves are too big to prevent the coffee grounds from getting stuck and plugging up the valve. This new design applies a “shut off” approach on the molds to manufacture much smaller ventilation holes.