Opaque Flat Pushbutton The 3SB35 series of pushbuttons are metal, round and have a mounting diameter of 22mm. This series of actuator are supplied with a holder. Pushbuttons with flat button Spring return or latching versions available Protection rating of IP67 PHASE OUT NOTIFICATION This product is in obsolescence mode and is due for discontinuation by the manufacturer. We recommend that you review the alternative range suggested by the manufacturer: SIRIUS ACT (3SU1). Please refer to the SIRIUS 3SB3 to ACT Cross-Reference guide located in the Technical Reference section. The Siemens 3SB3 series is a range of plastic and metal commanding devices for front panel mounting and rear wire connection. The 3SBB3 series of pushbuttons, selector switches and indicator lights are of a modern industrial design with a flat construction and are easy to install.