Check the listing for details. Behringer Flow 4VIO I/O Expander. Condition: New. Listed at 229.00 USD. Expand Your Flow 4V with Premium Preamps and Flexible I/O Do you want to bolster the I/O of your Flow 4V field recorder? Then you need the Behringer Flow 4Vio. Designed specifically for the Flow 4V, this I/O expander extends your input capabilities with four high-caliber mic preamps and two headphone outputs with dedicated Level controls. Moreover, you’ll benefit from the same dual-stage A/D converters and ample dynamic range that Sweetwater recordists have been raving about since we first deployed the Flow 4V. Additionally, the Flow 4Vio features a class-compliant USB audio and MIDI interface, as well as StageConnect multichannel audio transmission. Furthermore, you can use the Flow 4Vio to power a connected Flow 4V field recorder via a single XLR cable.