Propane / butane gas cutting torch

Propane butane

— gaseous fuel in the form of a mixture of pressurized light hydrocarbons, primarily propane (C3H8) and butane/isobutane (C4H10), hence the name. Such a mixture is not only easier to obtain than relatively pure propane or butane — it also has a higher flame temperature (2400 – 2700 °C versus 2100 – 2500 °C).