Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number TBS11-500-1-5-1 found under Trackball Data Entry by Bei Sensors And Systems Co Inc. The National Stock Number assigned to this part is 1290013301686, 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 TBS11-500-1-5-1.