| SINGLE GAS PORTABLE MODEL IQ-250 
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ISTs 
                    Model IQ-250 is a single gas portable instrument which can 
                    be equipped with either a solid state, or elec-trochemical 
                    sensor. Any one of over 150 toxic and combustible gases can 
                    be chosen. A digital display indicates the gas concentration, 
                    and an alarm buzzer and alarm LEDs alert you to the 
                    presence of hazardous levels. The IQ-250 does not incorporate 
                    a sample pump, and samples by diffusion only. User adjustable 
                    setpoints are provided for low, mid, and high alarm levels. 
                    The unit operates on 4 AA size alkaline or nicad 
                    batteries, or the AC adapter/charger. The IQ-250 weighs approximately 
                    22 ounces, including batteries.