What is the sleeve device for an E-1 in the Navy?

In the Navy, the designation "E-1" refers to a Seaman Recruit, the lowest rank in the enlisted sailor hierarchy. For an E-1, there are no insignia markings on the uniform sleeves to indicate rank. This absence of markings visually communicates that the individual is in the initial phase of their naval career and has not yet attained any rank that warrants the display of insignia such as stripes or chevrons.

Thus, the correct characterization of the sleeve device for an E-1 is that there is none, signifying their status as a recruit who is undergoing training and has not yet progressed to the next rank level where insignia would be appropriate.