Neutral Litmus pH test paper tests for Neutrality of a solution, or its acidity or alkalinity, does not come with a color chart, test strip will turn red if dipped into an acidic solution (pH <7) or blue if dipped into an alkaline solution (pH >7), Size: 100 test strips
conductivity tester, handheld device provides a qualitative visual indicator of the conductivity of different solutions, acids or salts, Two brass probes can be touched to a solid substance, or immersed in a liquid, to show conductivity on green LEDs
That provides accurate measurement of pH, oxidation-reduction potential(ORP), conductivity, salinity, and total dissolved solids (TDS).Starter pen meter are the economical option,Simple Operation in a Slim and Portable Design
DC Voltmeter, Full scale and fully enclosed, For numerous electrical experiments, Color-coded binding posts, Can be used with Banana cords, Voltage: 0 to 3V, 0 to 10V, 0 to 15V, Accuracy: +/-2.5%