what size lines

i cnat find what i want so im builidng my own kit. what size is the fitting that screws onto the selanoid the other end is a -4 an

that will depend on the solenoid you are using...some have 1/4npt and some are 1/8npt inlets

To tell which NPT threads your solenoid has, measure the diameter of the hole in the solenoid.

1/4" NPT = 0.405"

1/2" NPT = 0.540"