This spring is for a commander gun with a standard diameter guide rod.
ISMI is a contractor of the U.S. government and produces springs used in machine guns with incredibly high cycling rates. Also, the creator of ISMI springs obtained his knowledge from extensive research in the development of springs used in Indy car racing.
Warning: This product may be alloyed with trace amounts of lead and other elements which are known to the State of California to cause reproductive harm and cancer. To prevent exposure, do not alter the product by welding, grinding, etc. For more information, go to www.P65Warnings.ca.gov.
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