Full technical specifications of the product here !

This Bluelab EC Pen simply shows you if your plants are getting the right amount of nutrients and lets you know if any solution adjustments are needed. To feed your plants well, you need to know what you are feeding them! Measuring your conductivity every day is the best way to avoid over-diluting or over-concentrating your nutrient solution. Completely change the solution in your tank every 7 days. Top up the nutrient level between changes - so your plants always have the right amount of food. The Bluelab Conductivity Pen also measures the temperature of the solution, as root health is vital for a successful harvest. Temperature affects the growth rate and structure of the plant, so a solution temperature of 18-22°C is recommended.

• completely waterproof
• simple one-point calibration
• 1 year warranty
• Auto-off function to extend battery life
• 1 x AAA alkaline battery (included)
• EC measurement range: 0.0 - 10.0
• accuracy: ± 0.1 at 25°C
• Selectable units for conductivity and temperature ( EC/ppm , C°/F° )
• LCD display with backlight
• Checkmark indicating successful calibration
• Function to hold the measured measurements
• Low battery indicator