A sealing device for an air valve can include a seat; a valve device configured to seal against the seat, the valve device being a poppet and comprising a guide shaft defining a bore extending from the bottom end of the poppet to the top end of the poppet; and a lever arm including a button, removably coupled to the poppet, and configured to engage with and seal the bore of the poppet, the button including a first contacting portion and a second contacting portion.