Sirius Act is a modular system of control and signaling devices from Siemens that is designed with IP69K protection and, according to the manufacturer, is easy to use. Users can choose between pushbuttons and emergency stop buttons, selector and key-operated switches as well as audible and visual alarms. The portfolio in metal and plastic versions for front panel mounting can be flexibly combined with various rear-mounted contact and LED modules. The components are connected to the control system via AS-Interface, IO-Link or standard wiring. Thanks to anti-twist protection and a special snap-on concept, the devices can be mounted quickly and without errors in groove-free holes. The design of the devices makes it possible to assemble the front element and rear holder without tools using the snap-on concept; disassembly is carried out using a release lever. Users can choose from four design series depending on their requirements. The holders are fitted with the various actuators and detectors on the front, while the rear is equipped with slots for contact and LED modules. A maximum of three modules can be mounted next to each other and two contact modules can be mounted behind each other.