Neptune Probe ORP Double Junction

ORP PROBE
Replace your ORP probe or add another for another tank

Buy this probe if you are:

Replacing a worn out ORP probe 
Adding another tank to your system and purchased a PM1 to do so.
Double Junction probes will last longer- about twice a long.  A Single Junction Lab grade should be replaced in 12 months and a Double Junction Lab Grade should be replaced in 24 months.