This is an essential part of your setup.
This is the Standard sensor cable with 2 mm banana connectors for WE, CE, RE and ground including crocodile clips (red, black, blue and green) with a connector (Type LEMO) to your potentiostat. This cable is usually included in the purchase of a PalmSens or EmStat.
A LEMO and a TRIAD plug or receptacle are easy to differentiate, since the TRIAD plug has a screw thread. The EmStat3 and the PalmSens3 need this 4 pin LEMO plug. Also the MultiEmStats comprised EmStat3s need these cables as well as the EmStat3 4WE.