RevoReef Refractometer is equipped with Automatic Temperature Compensation (ATS) system. The ambient working temperature of the room must be 20°C (68°F) whenever the instrument is re-calibrated. Once calibrated, shifts in ambient temperature within the acceptable range (10°C - 30°C) should not affect accuracy.
 
• Provides accurate salinity readings in Specific Gravity (d 2020) and Parts-per-thousand (PPT) • Automatic Temperature Compensation (ATS) • Easy-focus adjustable Eyepiece • For Brackish and Marine aquarium • Easy to calibrate