Portable Tetra multi-gas monitor detects from 1 to 4 gases and uses a single button to control all functions. Backlit “at-a-glance” display provides simultaneous viewing of all gas readings, alarm conditions, and battery life. Despite its light weight and small size, the Tetra is very rugged with a rubber over-molding and flexible internal architecture. It is water and dust resistant to IP65; floats in water; and is UL, CSA, and ATEX-approved for use in hazardous areas. CEA Instruments, Inc., Emerson, NJ