●The 18KW thermostat is suitable for a pool with ≤ 424 ft³ / 12m³. ●The 5.5KW thermostat is suitable for ≤ 127 ft³ pool / 3.6m³. ●The 9KW thermostat is suitable for a pool with ≤ 212 ft³ / 6m³. ●The 11KW thermostat is suitable for a pool with ≤ 259 ft³ / 7.3m³.
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