Apera Instruments EC60-E probe is the replacement probe for Apera EC60 pocket conductivity tester. This probe features Apera's unique Brush-resistant Platinum Black (BPB) sensor, which ensures accurate conductivity measurement in a wide range (0 to 20.00 mS). Works great for regular water solution testing such as hydroponics, aquaculture, water/waste water treatment, pools and spas, etc.