The LEYRO LPG 300 is an automatic portable controller. This device is characterized as a self-generating and standalone portable controller that is applicable for calibration, test and verification of instruments. The LPG 300 can be used with a very low pressure. This device operates with a pressure ranging from 1 hPa up to 1000 hPa and has an accuracy range up to 0.1% FS. In addition to the said details, this device is equipped with a rechargeable lithium-ion battery that can be directed to the electricity network.