Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number R1923-02 found under Electron Tube by Hamamatsu Corporation. The National Stock Number assigned to this part is 5960013978328, and the Federal Supply Class is 5960 Electron Tubes And Associated Hardware. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like R1923-02.