This D.O.T. Rated 1/2" Male NPT to 1/4" Push to Connect Elbow Fitting gives you the ability to elbow off from a 1/2" port. And then connect a 1/4" air line to it.
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.