Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MODEL 8120 found under Test Kit Mask Protective by Tsi Incorporated. The National Stock Number assigned to this part is 4240016132263, and the Federal Supply Class is 4240 Safety And Rescue Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MODEL 8120.