is an extended version of the popular FluorPen, that offers measurement of equal fluorescence parameters and protocols – Ft, QY, OJIP, NPQ and Light Curve. Due to its robust and weatherproof construction the Monitoring Pen is designed for long-term, unattended monitoring of chlorophyll fluorescence parameters in indoor or outdoor experiments, even in challenging environmental conditions in polar regions or under water level. External battery ensures measurement in term of months or years.