Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 18-00063-05RM found under Compressor Unit Rotary by W W Williams Company The. The National Stock Number assigned to this part is 4310015823198, and the Federal Supply Class is 4310 Compressors And Vacuum Pumps. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 18-00063-05RM.