Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1660-21 PUTTY found under Organizer Wall by Rubbermaid Office Products Group Inc. The National Stock Number assigned to this part is 7520012880463, 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 1660-21 PUTTY.