Tuning FX regulator internal o-ring size?

I think one of these two drawings will have the information you are looking for. One is for a bottle gun and the other for a tube reservoir gun.

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View attachment F10101-eng.1608157387.pdf

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View attachment F10056-3-eng.1608157387.pdf

Chip


 
The first number is the inside diameter (ID) of the Oring... 4mm

The second number is the cross section (CS) of the Oring... 1.5mm

NBR70 is the material type and hardness of of the Oring... Buna-N Nitrile O-Rings (NBR) and 70 is the durometer (hardness) number.

Go to this website and you will learn more about Orings than you ever thought you wanted to know. Read under the "O-ring Information" area.

https://www.theoringstore.com/store/