The MSR Heat Exchanger increases the efficiency of your stoves up to 25 percent. The unique waffled design channels the heat from the stove up the sides of the pot to increase the heated surface area. Compatible with all MSR 1.5L and 2L pots (with the exception of the Titan 1.5L). When used with liquid fuel stoves, or those like the WindPro stove with remote burners, it can act as a wind block by extending below the pot.