Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 813-00521 found under Resistor Variable Wire Wound Precision by Engis Corporation. The National Stock Number assigned to this part is 5905002396791, and the Federal Supply Class is 5905 Resistors. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 813-00521.