Replacement Set Screw Plug, Polaris Edge Connectors, 2/0 – 14 AWG
https://dev.nsiindustries.com/product/replacement-set-screw-plug-polaris-edge-connectors-2-0-14-awg/
Polaris Multi-Tap Connectors feature removable plugs to cover the set screws used for tightening. This replacement plug fits into those ports to prevent debris, moisture and other contaminants from entering the connector.