Kanthal AF- is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1300°C (2370°F). The alloy is characterized by excellent oxidation resistance and very good form stability resulting in long element life.
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Kanthal AF
Kanthal A1- is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1400°C (2550°F). The alloy is characterized by high resistivity and very good oxidation resistance.
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Kanthal A1
It appears that it is very similar to A1, however I'm not sure what the resistivity of it would be in comparison..