Features:

• Highly efficient and accurate due to its advanced microprocessor technology
• Hold function -- saves measurements for convenient reading and recording
• Auto-off function -- automatically shuts off meter after 10 minutes of non-use to conserve batteries
• Display -- large and easy-to-read LCD screen
• Factory calibrated -- recalibration is not necessary, but can be done easily with a watch screwdriver

Easy to Follow Instructions!
Using a clean cup or glass, take a sample of your raw feed water. Remove the protective cap from the Tester. Push the "ON" button to activate LCD display. Submerse the tester's probes into the water sample and observe for approx. 10 seconds. Record the results. Repeat the same procedure with a sample of your reverse osmosis (RO) water. If the system is new or the membrane has been replaced, do not test the first tank of RO water. The first tank of product water will contain sanitizer and possibly carbon fines from your new filters. This will cause false reading. Use the following formula to calculate the percentage of solids (TDS) that your membrane is removing: