Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number EEP53A-1 2 IN. NPT found under Indicator Sight Liquid by Ernst Flow Industries Inc. The National Stock Number assigned to this part is 6680014134173, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like EEP53A-1 2 IN. NPT.