The Kessil A80 Unit Link Cable, 90 degree connector can be used to connect together unlimited Kessil LED Lights. It is offered mostly with the A80s in mind as the 90 degree connector is more attractive with those lights. All the lights daisy-chained together can be controlled by a single Kessil Spectral Controller or Neptune Apex Controller (or Apex Jr. & Apex Lite Controllers with the VDM Module). If you're using the Kessil without a controller the first light in the chain will control the dimming and spectrum for subsequent lights. 6 feet long.