Extech PH90 Waterproof PH Meter<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Simultaneous display of pH and Temperature</li><li>2 or 3 point calibration automatically recognizes buffer solutions (order pH buffers separately)</li><li>PTS (percent of slope) tells you when it's time to replace your electrode (below 70% or above 130%)</li><li>Automatic Temperature Compensation</li><li>Data Hold， Min/Max， Auto Power Off， and low battery indication</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31RoXQw61uL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/51--sPpx3hL.jpg" noproxy>