Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 542 20 66-73 found under Indicator Electrical Tachometer by Husqvarna Outdoor Products Inc. The National Stock Number assigned to this part is 6620015863456, and the Federal Supply Class is 6620 Engine Instruments. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 542 20 66-73.