The SGX VQ5MB is a gas sensor that operates on the principle of thermal conductivity to detect a range of gases and vapors at concentrations from 0 to 100% by volume. It features a matched pair of sensor elements, including a "closed can" compensator to improve accuracy, and has extended pins for direct mounting on printed circuit boards. The VQ5MB is designed for use in both portable and stationary gas detection applications, making it suitable for measuring combustible gases, as well as specific gases like ammonia, helium, and hydrogen.