A-M Systems Extracellular Amplifiers A-M Systems Extracellular Amplifiers Differential AC Amplifier Model 1700 Microelectrode AC Amplifier Model 1800 AC/DC Differential Amplifier Model 3000 16-Channel Extracellular Differential AC Amplifier Model 3500 16-Channel Extracellular Amplifier with Headstage Model 3600 MultiRecord High Density Recording Package Model 4000