Following the Axoclamp tradition, this amplifier model is a complete microelectrode current clamp and voltage clamp amplifier, useful for a wide range of intracellular microelectrode recording techniques. The Axoclamp™ 900A Microelectrode Amplifier represents the latest generation of our Axoclamp amplifier family. This model features many enhancements that improve its recording capability, make the amplifier easier to use, and help your experiments last longer. The Axoclamp 900A Microelectrode Amplifier provides the following modes of operation: I-Clamp: Current clamp using two independent bridge amplifiers for voltage measurements DCC: Discontinuous current clamp for accurate voltage measurements, even when the electrode resistance changes TEVC: High-compliance two-electrode voltage clamp for Xenopus oocytes and mammalian cells dSEVC: Discontinuous single-electrode voltage clamp for small cells with large currents HVIC: High-voltage current clamp for extracellular applications such as iontophoresis Excellent amplifier performance The ±180 V output compliance used for TEVC and HVIC modes makes it possible to pass larger currents and ensures faster clamp speeds. TEVC and dSEVC modes both have wide AC voltage clamp gain ranges for excellent voltage control. When DC Restore is enabled, the DC voltage clamp gain is greater than 1,000,000, ensuring optimal voltage control for constant-voltage measurements. The new dSEVC design is more stable and twice as fast as before, providing an excellent alternative to standard continuous single-electrode voltage clamping.