Silver Reed Curl cord For EC-1 and SilverKnit 4 Applications - This cord is the connection between the EC-1 and the Silver Reed SK-800 series knitting machine. If you have a functioning EC1 and the original cord is damaged and not repairable, this is the cord you need.
This cable is also needed to connect the SilverKnit 4 package to DesignaKnit, (the Silverknit 4 replaces the EC1 and PC1 completely). DesignaKnit must be used with the SilverKnit 4 package as it provides the drivers needed to make the machine knit in pattern.
So if you don't have a functioning EC1 but you do have a working curly cord, and you do have DesignaKnit, then the SilverKnit 4 package is what you need.