BestMounts Multi-Gang Box Extender: Easily make 2, 3, 4 or 5-gang extension , Single Solution for Single and multi-gang Extension eliminates the need to stock multiple SKUs, Will not rust or conduct electricity The Multi-Gang Non-Metallic Box Extender is designed to mount on non-metallic boxes to bring flush to the surface. This item is gangable, allowing configurations between 1-5-Gangs. Made of durable PVC material, the box extender is non-conductive and non-corrosive making it safe to install and resistant to weather and temperature. The Electrical Box Extender lends support to the contents of a wall box. This non-conductive extender helps prevent arcing by forming a barrier between the box and the metal screws on the device. This box extender has a 2-hour fire rating.