"WEIGHT 0.43 POUNDS; LIGHT EMITTING DIODE, SILICONE PHOTOCELL, FIXED WAVELEGNGTH; POWER SUPPLY; 4 AAAA ALKALINE BATTERIES; APPROXIMATE LIFE IS 500 TESTES; DISPLAY: LIQUID CRYSTAL; OPERATING TEMPERATURE: 0 TO 50 DEGREES C; SUITABLE FOR FIELD STUDIES OR ON THE SPOT PROCESSING MONITORING; MEASURES EVEN LEVELS OF CONSTITUENTS IMPACTING WATER QUALITY"