Heat ExchangerThe Heat Exchanger increases the efficiency of your stoves up to 25%. The unique waffled design channels the heat from the stove up the sides of the pot to increase the heated surface area. When used with liquid fuel stoves, or remote burner canister stoves like the MSR WindPro II, it can also act as a wind block because it extends below the pot. Compatible With: Pots 6. 6 in. 7. 3 in. (16. 8 cm 18. 5 cm) in diameter, including the MSR Alpinist 2 cook