The STR1 transponder safety switch has monitored semiconductor outputs (OSSDs) and can be safely connected either individually or in series. It can be used for applications where a high level of manipulation protection is required. The STR1 is available with three codes: universally coded, uniquely coded, and permanently coded. Universally coded sensors accept all actuators. An actuator must be taught into both the uniquely coded and permanently coded variants; this is the only actuator that the STR1 then accepts. The sensor has three active sensor surfaces, and actuators come in three different styles (standard, flat, and mini). This allows the STR1 to offer maximum mounting flexibility.