Sper Scientific water quality pens or testers are easy to carry, simple to operate and sufficient for most field pH tests. Highly stable and accurate readings with a large LCD display. Designed for simple one-hand operation. The cases are IP65 waterproof, and will float if accidentally dropped into the water.
Dissolved Oxygen Pen - 850045
Large Display ORP Pen - 850053
Large Display Salinity Pen - 850036
Large Display Conductivity Pen - 850037
Test Tube pH Pens - 850062,63,65,66,67
Large Display pH Pens - 850050,51,52