The main valve in the center is the oral inflation valve. You can press and blow into this valve to inflate the product. Additionally, you may also use an air compressor with a blow gun attachment to inflate the product through this valve.
The black rubber ball valve is used for inflation with a product that can accept an inflation needle like a recreational ball pump or bike tire pump.
The third valve, with the white mechanism inside, is the automatic pressure relief valve. This valve will activate at or above approximately 5.4 psi to bleed off pressure to prevent bladder damage and will close automatically once a safe pressure is reached. NEVER insert an inflation needle or other inflation product into this valve.