Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 658173-5-1 found under Parts Kit Vent Valv by B E Aerospace Consumables Management. The National Stock Number assigned to this part is 4820014891248, 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 658173-5-1.