Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 758-9905000-25661 found under Generator Tachometer by Automatic Timing And Control Co. The National Stock Number assigned to this part is 6680015146653, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 758-9905000-25661.