Match the number of channels you need to license when using Vista 3 Lighting and Media Control Software, with the Chroma-Q CQ678-1512 Dongle. This USB dongle attaches to your computer (Windows or Mac) running the Vista software and enables data output for control of your fixtures, or for tracking backup to another Vista system. You can use one dongle to match the number of channels you need to license when using Vista 3 Lighting and Media Control Software with this Vista 512-Channel Dongle. This USB dongle attaches to your computer (Windows or Mac) running the Vista software and enables data output for control of your fixtures, or for tracking backup to another Vista system. You can use one dongle to enable the number of channels you need or use multiple dongles attached to the same system to enable the sum of the attached dongles.