This Thermo Electron Orion 420A+ Basic pH/mV/ORP Benchtop Meter is in good condition and is guaranteed to be fully functional with a 30-day return policy. We urge customers to view all photos as they show overall condition, included accessories and useful information. Please feel free to contact us with any questions. The Orion 420A is a benchtop meter that gives you the basics for fast, accurate pH measurement. This system is ideal for a busy, multi-user laboratory or plant environment. Calibration is fast, easy and accurate with autocalibration using built-in Auto-Buffer-Recognition, built-in buffer/temperature tables, and automatically calculated and displayed electrode slope value. The mV mode makes ORP measurements fast and reliable. The Model 420A is equipped with RS232 communications that allow the user to record data using the optional Orion Model 900A Printer or a computer. Features: - Autocalibration with Choice of 3 Buffers - ROSS Resolution(tm) to 0.001 pH Units - Simultaneous pH and Temperature Display Meter Specifications pH Range: -2.000 to 19.999 pH Resolution: 0.001/0.01/0.1 pH pH Relative Accuracy: +/- 0.005 pH Slope: 80 to 120% pH Auto-Buffer Recognition: 4.01, 7.00, 10.01 Temperature Range: -5.0 to 105.0C Temperature Resolution: 0.1C Temperature Relative Accuracy: +/- 1.0C Millivolts Range: +/- 1600.0 mV Millivolts Resolution: 0.1 mV Millivolts Relative Accuracy: +/- 0.2 mV or +/- 0.05% of reading, whichever is greater Relative Millivolts Range: +/- 1999.9 mV Relative Millivolts Resolution: 0.1 mv Relative Millivolts Relative Accuracy: +/- 0.2 mV or +/- 0.05% of reading, whichever is greater Buffer recognition Automatic at pH 4.01, 7.00, 10.01 Output RS-232 Display Custom LCD Agency Approvals CE, CSA, UL Probe: Orion 9810BN Micro pH Electrode Glass Combination Micro-pH Electrode for use in gels or smaller sample volumes. Requires only 0.5 µL of sample. BNC connector, 1 m cable. Specifications: pH range: 0 to 14 Temperature range: 0-80C Type Reference: Ag/AgCl 9Vdc Power Supply Included Orion 420Aplus