The Oakton® CON 400 standard conductivity and TDS meter is a handheld, waterproof, and dustproof meter that has dual-line, simultaneous display of EC and TDS readings. The meter is commonly used to measure conductivity and TDS of a substance in pure and sea water testing and treatment, and in laboratory and industrial applications. This meter features single- or multi-point, push-button calibration with auto-ranging across five ranges, with one point per range, for fast response and resolution across a wide range of results. The meter has choice of manual or ATC for accuracy. It has a built-in memory with storage for up to 50 readings, Good Laboratory Practices (GLP)-approved date and time stamping, and IrDA wireless technology for data communication. The SETUP mode lets you customize meter parameters. Selectable auto-endpoint feature automatically freezes reading when it stabilizes. Other features include Hold function, Ready indicator, self-diagnostic error messages and automatic shutoff after 30 minutes of non-use. Setup mode lets you customize meter parameters. Real-time clock stamps calibration data and stored data with time and date (month and day). All replacement probes have a built-in temperature sensor. Cable length of 3 ft. The meter is 7.5 (l) x 3.5 (w) x 1.75 (h) inches, and weighs 1.0 lb. It has up to 200 hours of continuous use with four 1.5-V AAA batteries (not included), or an AC adapter (not included) and comes with probe 35608-50 (K=1.0).