KPM Aqua-Boy KAFI [KAFI] Coffee Moisture Meter (No Electrode). The KAFI range of coffee bean moisture meters are calibrated and tailor made specifically for the coffee industry. Aqua-Boy moisture meters analyse the moisture content of solid materials in a host of applications. Easy to use and highly portable, these compact meters deliver instant results with an accuracy of 0.1%. Recommended by official test and research laboratories, Aqua-Boy moisture meters are the automatic choice of industrial specialists and scientists worldwide