Extech ph100 ph meter 0 14ph ip57 extech ph100 the extech ph100 ph meter is a robust watertight ip57 ph tester its flat changeable measurement electrode allows measurements in liquids semi solids at low flow levels and even on surfaces the flat electrode also eliminates electrode breakage and clogged junctions the readings are temperature compensated for greater accuracy and the ph and temperatue are displayed simultaneously as well as the digital ph display there is also a use