Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number D4-050-27 found under Ball Check by Skytron Llc. The National Stock Number assigned to this part is 4820014624317, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like D4-050-27.