[. . . ] Operating Instructions EcoTestr pH 2 Waterproof Pocket Tester Conditioning Before First Use: Precipitation of the sensor electrolyte may cause white crystals to form around the cap. [. . . ] To obtain your second and third calibration points, proceed to the next buffer value (pH 4. 00 or pH 10. 00) and repeat step 3 - 6 8. In harsh samples, take readings quickly, then rinse sensor with de-ionized water immediately to remove residues and prevent electrode contamination Useful Notes: 1. To avoid cross contamination, rinse between samples and calibration standards with de-ionized water 2. To maintain tester accuracy, use tester regularly or calibrate at regular intervals as required 3. For long-term storage, fill cap with 20 mm of storage solution (NOT de-ionized water) and replace cap*. This will keep sensor conditioned and ready for next use * The tester cap is not leak-proof. To remove batteries, lift up the front battery cover to release the front catch. Next, lift the pocket clip to release the back catch and slide upwards to remove the battery cover (Figure 1) 3. [. . . ] Accessories: Eutech Order Code ECBU4BT ECBU7BT ECBU10BT ECRE005 ECDPCBT Oakton Order Code 00654-00 00654-04 00654-08 00653-04 00653-06 Description pH 4. 01 buffer solution, 480 ml bottle pH 7. 00 buffer solution, 480 ml bottle pH 10. 01 buffer solution, 480 ml bottle Storage solution for pH sensor, 480 ml bottle Protein remover solution, 480 ml bottle [. . . ]