Description Description The Haskel 27375-5V stem is a vulcanized valve stem that is compatible with Haskel 8AGT-5/30 gas boosters. This stem is designed to provide reliable and precise control of the pilot valve, which regulates the flow of gas into the booster. State of California Proposition 65 WARNINGCancer and Reproductive Harm - www.P65Warnings.ca.gov. Literature & Docs Accessories