You just got to the river, beach, or lake and you are ready for a fun day with the family or friends. You pull out your inflatable and pump, when you try and hook up the pump to inflate you find your Boston Valves is cracked or even missing! Don&';t ruin a great day Always carry a spare! The 2 Boston valves have different thread patterns. One is sure to fit the thread pattern of your inflatable, no matter what brand. They have square bases, which are much easier to turn than round, especially with wet hands. Boston valves allow you to inflate the towable without losing any air that is already in the tube. It does this with a double cap system. One cap opens to a one way valve that only lets air in, but won&';t allow it to escape. When you need to deflate the tube just remove both caps and the tube will deflate easily.