Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number FSF 2520T found under Transistor by Sertech Laboratories Inc. The National Stock Number assigned to this part is 5961014439089, and the Federal Supply Class is 5961 Semiconductor Devices And Associated Hardware. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like FSF 2520T.