Twin (double) 2 way 250w (watt) dimmer. Appropriate for Mains or Low Voltage lighting up to 250w (watt) per dimmer fits standard (established by authority) 1G (Gang) 25 millimeter (mm) Back Box * appropriate for Mains or Low Voltage Lighting * Up to 250w (watt) per Dimmer * Fits standard (established by authority) 1G (Gang) 25 millimeter (mm) Back Box p=68.98%