Comparison between the PH probe at 78 euros and the PH Expert probe at 59 euros for the Zodiac PH Expert regulator.

Client:
I have the Zodiac PH Expert regulator. What is the difference between the PH probe for 78 euros and the PH Expert probe for 59 euros?

Technical Advisor:
Hello, can you send me a photo of your current probe? I will check which one you need.