Check the original measurements.

As small as possible. The p-port itself and a cell have given sizes.

Only in the breathing bag or the hose you can check real ppO2!

Connecting to the scrubber you have not actual ppO2 from what you breath (see funktion of the scrubber for more info) You see exhale ppO2! As fresh gas is injected into breathing bag after scrubber!! And lifetime of sensor increases due to less moisture in breathing loop compared to scrubber of course.

 

    Left picture

If not in use, plug it with p-port plug!

No remarkable difference in hose lenght because sensor is built to the back,
so gas passes perfect the sensor!