Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1 5-1660FB found under Valve Vent by Robert H Wager Companyinc. The National Stock Number assigned to this part is 4820013019085, 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 1 5-1660FB.