Return line fittings

[FreightTrain]

What size are the threads in the injectors for the return lines?I am gonna replace all my T fittings with normal double ended Compression sleeve fittings but need to know the thread size.I am thinking 1/4NPT but not sure.

 

[WillWagner]

1/8 NPT into the injectors. You can buy the correct hose and fittings from McMaster. When the stuff is new, it's beautiful!

 

[m-35tom]

but they already are double ended compression fittings...........