Insulation testers used to be bulky, heavy and difficult to lug around. Yet Fluke's 1587 and 1577 insulation multimeters combine a 1-kV digital insulation tester with a full-featured true-RMS digital multimeter in a DMM-size (digital multimeter) package. The 1587 tests insulation resistance to 2 GW at five output voltages from 50 to 1000 V. The 1577 tests up to 600 MW of resistance at either 500 or 1000 V. Insulation testing is disabled if the meters are connected to a live circuit with more than 30 V. After testing, the meters automatically discharge all capacitive voltage from the equipment under test to prevent accidental shocks. The included probe permits one-handed testing via a trigger on the probe handle. Both DMMs measure ac-dc voltage, milliamps, dc millivolts, resistance, and continuity. The 1587 adds capacitance, diode test, frequency, low-pass filter, min/max, and temperature functions. The 1587 costs $549, and the 1577 lists at $449.