Panel-mounted light indicator for rectangular panel hole template with quick-fit device. The lens is inserted from the front of the panel and fits into the body of the indicator positioned on the back of the panel, in correspondence with the drilling template. The indicator is positioned parallel to the panel, so as to reduce the internal bulk. Solution adaptable to different final applications: household appliances, HoReCa instrumentation, HVAC-R, lighting, industrial automation, electrical panels, mobility.