Replacement Electrode Module Testing Parameter pH pH Range 0 to 14 Tip Shape Flat Operating Temp Range 32 Degrees to 122 Degrees F Body Material Polycarbonate Diameter 16mm Length 38 mm Temp Sensor -5 Degrees to 90 Degrees C For Use With Extech PH100 Waterproof pH Pen Shelf Life 1 yr Electrolyte KCL Recommended Use Liquids Semi-Solids Solids Includes Cap Manufacturers Warranty Length 6 mo