Our Ion-Selective Electrodes (ISEs) are double junction combination electrodes and do not require an external reference electrode. 

The Ammonium Ion-Selective Electrode measures levels of ammonium ions. It can also indicate aqueous ammonia levels if sample solutions are acidified to convert NH3 to NH4+.

Electrodes are combination-style, non-refillable, and gel-filled.

It is important for you to know that Forston Labs ISE membranes, like all other PVC ISE membranes, have a limited life expectancy; however, the replaceable module of Forston Labs ISEs allows you to simply discard the used one, and replace it with a new module. We recommend that you do not purchase replacement modules far in advance of their expected time of use, as their life expectancy is limited as well.

Two calibration standards and a short-term soaking bottle are included.