Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 18-000-853 AND18-000-855 found under Parts Kit Ball Valve by Ardox Corp. The National Stock Number assigned to this part is 4820011221782, 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 18-000-853 AND18-000-855.