Electric Vacuum Pen From Aquarium Air Pump.

Step 7: Gently Pry Out The Gasket

We are going to gently pry out the gasket here.  Notice that it's attached to a little white notch at the bottom when pulling it out.

To reverse the air flow we need to flip this gasket around 180 degrees.   To do this we will need to punch a hole in the opposite end for that white peg to go through.