RasPi Environmental Sensor Bundle
get a free RaspberryPi 3!

The bundle comes with the Tentacle T3, a RaspberryPi HAT to host 3 EZO circuits. The bundle always comes with an RTD circuit and a PT-1000 probe for  temperature compensation. For the 2 isolated channels you can chose 2 additional sensor bundles that include probes, calibration solutions and everything you need to get started. Chose 2 of pH, Conductivity, ORP and Dissolved Oxygen.

And the RaspberryPi 3 Model B is included for free!