Electrophysiology is study of the flow of ions in living tissue, that is the electrical properties of cells and tissues, measuring voltage change of a biological entity from a single ion channel proteins to an organ (for example, heart). Microelectrodes (glass pipette filled with an electrolyte) are placed inside a single cell for intracellular measurement and near the surface of a cell or in a preparation for extracellular measurement. Wide range of products include: electrodes, stimulators, data acquisition systems, cardiophys ECG, intracellular/extracellular recording, voltage clamp for ussing, stimulation and isolation, optogenetics, digital filtering.