INDICATED USE: Gamma survey DETECTORS: Two internal energy compensated G-M tubes ENERGY RESPONSE: Within plus or minus 15% of true value from 60 keV - 3 MeV SATURATION: In excess of 1000 R/hr METER DIAL: 0 - 2 mR/hr, BAT TEST MULTIPLIERS: X0.1, X1, X10, X100, X1000 LINEARITY: Reading within plus or minus 10% of true value with detector connected AUDIO: Built in unimorph speaker with ON/OFF switch (greater than 60 dB at 2 feet ) CALIBRATION CONTROLS: Accessible from front of instrument (protective cover provided ) HIGH VOLTAGE: Adjustable from 200 - 1500 volts THRESHOLD: 30 mV plus or minus 10 mV RESPONSE: Toggle switch for FAST (4 seconds) or SLOW (22 seconds) from 10% to 90% of final reading RESET: Push-button to zero meter POWER: 2 each "D" cell batteries (housed in sealed compartment that is externally accessible ) BATTERY LIFE: Typically 600 hours with alkaline batteries (battery condition can be checked on meter )