The L61QB21 is a twin-touch flush-projecting pushbutton operator head designed for industrial control applications with spring return functionality and non-illuminated operation. It features a compact flush-projecting design with dimensions of 53.9 mm overall length, 17 mm projection, and 43 mm width, providing an IP66 degree of protection suitable for demanding industrial environments. The unit incorporates dual-position touch buttons with green (NO) and red (NC) contact configurations, available with international symbols or text markings (START/STOP). This operator head is commonly used in control stations, emergency stop systems, and industrial machinery control panels where reliable, weather-resistant pushbutton operation is required.