MSR ISOPRO Fuel Cartridge
MSR ISOPRO is a mixture of isobutane and 80/20 propane that improves performance, with the purest isobutane (5% or less n-butane) of any box fuel. This clean combustion formulation maintains higher internal pressure at lower temperatures than standard butane / propane mixtures, offering superior cold performance and more constant production during the life of the box.
