This is 3/8" Male NPT and Splits off to 4 5/16" Push To Connects. We call this Fitting our Banjo Fitting.
This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.p65warnings.ca.gov.
I was helped locating a part I needed for my nightmare edition system and it was sent immediately. Great company!!
I ended up ordering the wrong size but used an adapter and works great.