The Polaris SP500 Set Screw Plug is a replacement part that take the place of the secure removable plugs present in many Polaris pre-insulated connectors. This plug fits connectors sized for 500 MCM wires, covering the set screws used to tighten their connections. Protect the interior of your Polaris pre-insulated connectors, each port of which is pre-loaded with an oxide inhibitor to ensure a low-contact resistance connection, by guarding the set screws from outside contaminants. Polaris designs connector