Made of virgin, high impact polyethylene. Designed to eliminate moisture collection. Large wire channel accommodates all wire sizes including the heaviest barbed wire, the lightest gauge smooth wire and Red Snap'r electric fence wire. Simple one nail installation made easy with 45° front loading feature. Provides long arcing distance protection from wire to post. Raised boss for easy removal of nail with a claw hammer. Four raised ribs imbed themselves into wood post so insulator will not twist.