BOTH ENDS HAVE 1-5/16" ACME (SAME AS BBQ TANK) AS WELL AS INTERNAL LEFT HAND THREAD (POL)USE AS A UNION OR EXTENSION BETWEEN TWO ACME OR POL FITTINGSASSEMBLY REQUIRED FREE SHIPPING DOMESTIC SHIPPING WARNING: This product can expose you to chemicals including lead and lead compounds, which are known to the state of California to cause cancer. www.P65Warnings.ca.gov. WARNING: These products contain a chemical known to the state of California to cause cancer and birth defects or reproductive harm. www.P65Warnings.ca.gov.
