What you need is a USB cable with the flat "Type A" connector on both ends, which is somewhat uncommon.
Most cables will be 12' and under, as the USB design spec requires boosters for longer cables.
Apex devices use the USB cable format, but they're not actually USB devices, so cables with boosters won't work.
If you need cables longer than 12', you can custom order cables through places like CablesToGo - just mention AquaBus in the comments.