Exhaust in Solenoids

[FRC Team CC]

Hey Teams!

Is there any way to block the exhaust holes on the sides of the solenoids (some screw or contraption)? We are trying to program a piston to move out and in and found the exhaust hole leaking out air.

Also, if we want to control both the A and the B holes, do we need a double solenoid? Or can we make do with a single solenoid?

Sorry about these simple questions; we are a new team and are trying to figure out all of these new components. We greatly appreciate your help.

Thanks,
Charging Champions