The interstage release mechanism is a simple expanding tube that installs in a hole at the top of your booster stage bottle.
When you inflate the booster stage, air passes through the pinholes at the top of this tube to fill the upper stage. The air
pressure inside the tube expands it so that it holds on to the inside of the upper stage nozzle. After liftoff, when the
booster stage is empty, the tube shrinks back to its original diameter and is pushed out by the pressure in the upper
stage. Make sure you also get a sustainer nozzle to work with this. Comes with detailed instructions.
Useful for making water rockets, pop bottle rockets, water bottle rockets, pop bottle water rockets, water pump rockets, soda bottle rockets and bicycle pump rockets.