AZ Waterproof EC pens Ideal for testing the EC / TDS / PPM levels in your Airgarden (aka the nutrient density of your water). For more information on EC levels and using an EC pen click here.

Raise the bar in ease of use, reliability, function and price point. AZ meters provide a big IP65 LCD screen with dual EC and temperature display. Wide measuring range from 0-9999ppm and a temperature range of -5°C to +60°C. Waterproof IP65 keypad with simple calibration. Also includes a hold button to freeze current readings in low visibility. ATC (auto temperature compensation) ensures accurate readings in all climates. Auto off function maximizes battery life.