This items includes 4 Enersol Header End Connector (HEC). The HEC can be used as a connector at the inlet and outlet of the bank or as a spacer in the bank to bridge an object on the roof (i.e. skylight)
If you are going to replace the HEC you should also replace the o-rings on each HEC. O-rings should never be reused.
Two o-rings are required per HEC.
Inspect your clips to ensure they are all in good condition