The IP 400 digital station 16-700184807- adds 16 digital station ports to the IP403, IP406 and IP412 base units to support 44 and 64 series and 2420 digital terminals. All Avaya IP Office expansion modules include a Power Supply Unit, Power Cord, the base unit and a Interconnect Cable (Blue, for linking back to base unit)
http://www.digitcom.ca/index.asp?PageAction=VIEWPROD&ProdID=37