Soda Bottle Pump Cap

Ever open a 2 liter bottle of soda only to find it went flat:(. Well not anymore, my mission was to make the world a bubblier place:) My thing will allow one to pump air into a soda bottle to increase pressure so you lose less CO2 or better know as bubble\'s. Also could be used as a scientific tool as a pressurization/depressurization chamber. This is a prototype and may need tweaking if it doesn't work i know i can get it to by tweaking and maybe use of 1 o-ring.