RLS/BP MX series burners are characterised by a modular monoblock structure that means all necessary components can be combined in a single unit thus making installation easier, faster and, above all, more flexible. The series covers a firing range from 1250 to 4500 kW, and they have been designed for use in hot water boilers, overheated water boilers as well as steam boilers. Burners working is 2 stages on the oil side and two stages progressive on the gas side. Alternatively the gas working can be modulating with the installation of a PID logic regulator. Using a particular proportioning gas valve the burner keeps the desired air/gas ratio in every working condition. The innovative combustion head which is able to reach good performances in term of Low NOx either during gas working or light oil working and reducing noise.