RKI 4-Gas Monitor GX-3RThe GX 3R is the worlds smallest 4 gas monitor weighing only 3. 52 ounces and can comfortably be clipped within a workers breathing zone (2. 2 W x 2. 55 H x 1. 02 D). It simultaneously monitors and displays LEL combustibles, O2, CO (Hydrogen compensated CO also available), and H2S. The GX 3R represents the latest evolution of gas detection technology utilizing a new generation of micro sensors. The LEL sensor has a unique design with two active