22 mm Twin Push Button Heads The 3SU1 series from Siemens offer a wide variety of quality, high performance twin push buttons for a multitude of applications. The 22mm modular range of twin push buttons are available for front panel mounting and rear conductor connection. Siemens Sirius Act Range The SIRIUS ACT range of push buttons and signalling devices presents an expertly designed selection of push buttons, pilot lights and switches that are intelligent, reliable and physically robust. An innovative snap-on concept makes the task of installing a unit so effortless that it can be done with one hand. Made with real metals and high-grade plastics, installed with smart functions and interaction abilities, these state-of-the-art push buttons, indicator lights and switches have been extreme element tested to guarantee a long usage life and reliability for all your operations. One-handed installation without special tools Components can be snapped on without having to hold the other side Installation possible in a slanted position Modular concept Stylish design & high-quality materials Extremely Rugged & Reliable Flexible Communication - AS-I, IO Link and Profinet