Ruggedness\nits ruggedness is unmatched by any similar pocket size tester. the uniquely re-enforced glass sensor can withstand accidental drop and shocks\n\none-touch calibration\non activation, the tester recognizes ph buffers at 7, 4, 10 and calibrates the end-point automatically.\n\nauto-end point\nthe auto-end point eliminates guesswork. the tester automatically senses a stable end-point reading and freezes it for recording.\n\nhold function\nable to freeze display for ease of reading and recording.\n\nrange: 0 to 14 ph\nresolution: 0.1 ph \n