Keystone insert provides a simple and elegant solution to handle unused openings in your keystone panels, racks, and wall plates Made from impact-resistant and fire-retardant high-temperature Thermoplastic These blank keystone insert ensures a clean professional look to your installation and provides necessary protection from dust and debris in unused keystone ports The sturdy construction ensures that these keystone insert will stand the test of time and can be reused and repurposed as necessary Sold in multipacks to provide you with an economic solution every time