Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number SR6F20 found under Spark Plug by Zeller Corp The. The National Stock Number assigned to this part is 2920002883126, and the Federal Supply Class is 2920 Engine Electrical System Components Nonaircraft. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like SR6F20.