Over and above the standard AC/DC voltage, current and resistance measurement functions, these high performance DMMs measure frequency, capacitance, conductance, and duty cycle (useful for pulse width modulators). They also include a continuity beeper, diode test, and analog display (43-segment analog bar graph and zoom on Models 83 and 85; high resolution analog pointer for changing or unstable signals on Models 87 and 87E). The 80 Series III meters also incorporate useful features such as min-max-average recording and a min-max alert beep for locating intermittents. A Touch-Hold® feature senses a stable reading and then locks it on the display for viewing after the test probe has been removed. A relative mode is provided to measure the deviation of readings from a previously stored reference. And finally, to prevent damage to the meter, an input alert safety feature (while measuring voltage or resistance) warns the user when the test leads are connected to the current jack. Four models are available. Model 83 has a 3-3/4 digit, 4000-count LCD display plus 0.1% basic VDC accuracy, and provides AC voltage and current measurements that are average sensing and RMS indicating. Model 85 has 0.08% accuracy and adds true-RMS AC voltage and current measurements. Top-of-the-line Models 87 and 87E offer high performance features such as 0.05% basic VDC accuracy, high-resolution 4-1/2 digit (20,000-count) display mode, fast (250ms) peak hold, and true-RMS AC voltage and current measurements. All four models have inputs that are protected to IEC 1010-1 category III 1000V rating with overvoltage transient protection to 8kV. Current inputs are protected with high energy fuses, including the 10A range. Models 83, 85 and 87 come with standard TL75 test leads. Model 87E comes with 63"-long TL24 electrician's test leads with an industrial alligator clip and detachable probe tips designed to fit in wall sockets and tight spots. All models include splash-proof and dust-proof case, bright backlit display, 9V battery, protective holster, operator's manual, and lifetime warranty. Size: 7.35"H x 3.41"W x 1.25"D. Weight: 12.5 oz.