Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 7530-01-042-7400STYLE 535 PLAIN found under Envelope Mailing by Bowers Envelope Company Inc. The National Stock Number assigned to this part is 7530010427400, 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 7530-01-042-7400STYLE 535 PLAIN.