Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number EEP501 3 4IN.OD 44IN. LG found under Shield Gage Sight Liquid Indicat by Ernst Flow Industries Inc. The National Stock Number assigned to this part is 6680013958510, 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 EEP501 3 4IN.OD 44IN. LG.