Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number PR340B-1PC78 found under Worm Shaft by The Electric Tachometer Corp. The National Stock Number assigned to this part is 3040009867320, and the Federal Supply Class is 3040 Miscellaneous Power Transmission Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like PR340B-1PC78.