Attributes . Sense Gas Twice Faster Than The Industry Average with Xcell Sensors, Survives 25 Drops From 4 ft (1-1/4m), MIL-STD-810G Drop Protection, 4 yr Instrument and Sensor Warranty, Motion Alert Option Tells Others That User Has Become Immobile, Bump and Calibrate with 1/2 The Test Gas and In 1/2 The Time Vs. Industry Average . Names