Description :<br>ORP-169E Tester Redox Water Quality pH Measurement Test Tool<br>Specification :<br>Measuring range : 0~&amp;plusmn;1999mVAccuracy : &amp;plusmn;5mVResolution :1 mVDisplay : 4-digital LCDPower Supply : 4 &amp;times; 1.5V(AG13)Dimensions : 188 &amp;times; 35 &amp;times; 35(mm3)Weight : 118g<br>How to use :1. Pull out the cap2. Click the button on\/off，and insert the plug into the liquid.3. When the reading is steady，click the button &amp;quot;Hold&amp;quot;，then，get the result4. After use，clear the plug.<br>Package includes :<br>1 x ORP-169E Redox Measurement Test Tool1 x Screw driver for open1 x English use manualComes in retail box :)<br>Details pictures :