The SM6T30CA is a Transil (or transient voltage suppressor) Diode manufactured by STMicroelectronics. Its rating is 600 watts, which means it can handle high-power loads up to that level. It can work with input voltages of up to 30 volts, and it has a current rating of 14.5A. This diode is bidirectional, meaning that it can work in both directions, and it has a tolerance of 5% for efficient circuit protection. It is also available in an SMB package for easy installation.