"The standard CIS pressure fitting is 12-mm x 1.5 and the fittings for the delivery and return lines have 14-mm x 1.5. So you will need an adaptor (12-mm x 1.5/14-mm x 1.5) to connect the CIS pressure gauge kit."
FYI - I have this adapter fitting in stock if anyone needs one.
Len.Cummings @ verizon.net