Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number R63870C11E8394-1 found under O Ring by Unifab Industries Inc. The National Stock Number assigned to this part is 5331002394922, 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 R63870C11E8394-1.