The BOOST CHECK only works for Gen 5+ can exits. If Gen 4 & 5 get PCV valve assembly.
These are the fittings which mount directly to the Gen 4 can wall which is threaded 7/8-14 SAE O-ring otherwise known as -10AN Port
-the boost check option only works with GEN5 + 'super center's
-for crankcase ventilation HP ratings are: 3/8" barb or -6AN=600HP capacity, 1/2" barb or -8AN=800, -10AN=1000, and 12AN=1200HP maximum.
Made in the USA!