The AD-17E from Zoom is a 5 VDC USB AC adapter used to power the F1, F6, H1, H1n, H2n, H5, H6, R8, Q2HD, Q4, Q4n, Q8, U-22, U-24, or U-44.
Note: This is a replacement adapter for the R8 recorder. It is a separately sold accessory for the F1, F6, H6, H2n, H1, H1n, and Q2HD recorders, as well as the U-22, U-24 and U-44 interfaces.