Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number R4120E101 found under Air Conditioner by Unifab Industries Inc. The National Stock Number assigned to this part is 4120002253791, and the Federal Supply Class is 4120 Air Conditioning Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like R4120E101.